All C Program

 

HELLO WORLD

//C hello world example
#include <stdio.h>
 
void main()
{
  printf("Hello world\n");
  
}

PRINT AN INTEGER

#include <stdio.h>

void main()

{

int number;

printf("Enter an integer: ");

// scanf() reads the formatted input and stores them

scanf("%d", &number);

// printf() displays the formatted output

printf("You entered: %d", number);

}

ADDITION OF TWO NO

#include<stdio.h>
 
void main()
{
   int a, b, c;
 
   printf("Enter two numbers to add\n");
   scanf("%d%d",&a,&b);
 
   c = a + b;
 
   printf("Sum of entered numbers = %d\n",c);
 
   
}

AREA OF RECTANGLE

#include<stdio.h>
 
void main()
{
   int length=2, breadth=3 ,area;
 
  
 
   area = length * breadth;
 
   printf("area of rectangle = %d\n",area);
 
   
}

CHECK NO IS ODD OR EVEN

#include <stdio.h>
 
void main()
{
   int n;
 
   printf("Enter an integer\n");
   scanf("%d", &n);
 
   if (n%2 == 0)
      printf("Even\n");
   else
      printf("Odd\n");
 
   
}

ADD SUBSTRACT MULTIPLY DIVIDE

#include <stdio.h>
 
void main()
{
   int first, second, add, subtract, multiply;
   float divide;
 
   printf("Enter two integers\n");
   scanf("%d%d", &first, &second);
 
   add = first + second;
   subtract = first - second;
   multiply = first * second;
   divide = first / (float)second;   //typecasting
 
   printf("Sum = %d\n",add);
   printf("Difference = %d\n",subtract);
   printf("Multiplication = %d\n",multiply);
   printf("Division = %.2f\n",divide);
 
   
}

ADD N NUMBERS

#include <stdio.h>
 
void main()
{
   int n, sum = 0, c, value;
 
   printf("Enter the number of integers you want to add\n");
   scanf("%d", &n);
 
   printf("Enter %d integers\n",n);
 
   for (c = 1; c <= n; c++)
   {
      scanf("%d", &value);
      sum = sum + value;
   }
 
   printf("Sum of entered integers = %d\n",sum);
 
   
}

GREATEST AMONG 3 NO

#include <stdio.h>
 
void main()
{
   int n1=2,n2=3,n3=4;
  
   if(n1>n2 && n2>n3)
   printf("n1 is greater"); 
   
   if(n2>n1 && n2>n3)
   printf("n2 is greater");
  
   if(n3>n1 && n3>n2)
   printf("n3 is greater");
 }  

SWAPPING 2 NO USING 3RD VARIABLE

#include <stdio.h>
 
int main()
{
   int x, y, temp;
 
   printf("Enter the value of x and y\n");
   scanf("%d%d", &x, &y);
 
   printf("Before Swapping\nx = %d\ny = %d\n",x,y);
 
   temp = x;
   x    = y;
   y    = temp;
 
   printf("After Swapping\nx = %d\ny = %d\n",x,y);
 
   return 0;
}

SWAPPING 2 NO WITHOUT USING 3RD VARIABLE

#include <stdio.h>
 
int main()
{
   int a, b;
 
   printf("Enter two integers to swap\n");
   scanf("%d%d", &a, &b);
 
   a = a + b;
   b = a - b;
   a = a - b;
 
   printf("a = %d\nb = %d\n",a,b);
   return 0;
}

PROGRAM USING SWITCH CASE

#include<stdio.h>
 
void main()
{
   int n;
 
   printf("Enter a number from 1, 2 or 3.\n");
   scanf("%d", &n);
 
   switch(n)
   {
      case 1:
              printf("You choose case 1 Thanks!\n");
              break;
      case 2:
             printf("You choose case 2 Thanks!\n");
              break;
      case 3:
              printf("You choose case 3 Thanks!\n");
              break;
 
      default:
              printf("You didn't did what i said.\n");
   }
 
   
}   

CALCULATE PERCENTAGE

#include<stdio.h>
 
void main()
{
  int total_mark=100, score=70,percentage;
 
   percentage=score/total_mark *100;
   
              printf("You percentage is %d",percentage);
              
   
}   

CALCULATE GROSS SALARY

#include <stdio.h>
 
int main()
{
    float basic, gross, da, hra;
 
    // Read basic salary of employee
    printf("Enter basic salary of an employee: ");
    scanf("%f", &basic);
 
 
    // Calculate D.A and H.R.A according to specified conditions
    if(basic <= 10000)
    {
        da  = basic * 0.8;
        hra = basic * 0.2;
    }
    else if(basic <= 20000)
    {
        da  = basic * 0.9;
        hra = basic * 0.25;
    }
    else
    {
        da  = basic * 0.95;
        hra = basic * 0.3;
    }
 
    // Calculate gross salary
    gross = basic + hra + da;
 
    printf("GROSS SALARY OF EMPLOYEE = %.2f", gross);
 
    return 0;
}

CALCULATE SIMPLE INTREST

#include<stdio.h>
 
void main()
{
  int amount=2000,rate=20,time=2,si;
 
   si=(amount*rate*time)/100;
   
              printf("You simple interest is %d",si);
              
   
}   

PRINT NO UP TO 10 USING FOR LOOP

#include<stdio.h>
 
void main()
{
  int i=0;
 
   for(i=0;i<10;i++)
   
              printf("%d /n",i);
              
   
}   

PRINT NO UP TO 10 USING DO WHILE LOOP

#include<stdio.h>
 
void main()
{
  int i=0;
 
  do
         {
              printf("%d /n",i);

               i++;
            }  
   while(i<11)
}   

PRINT NO UP TO 10 USING WHILE LOOP

#include<stdio.h>
 
void main()
{
  int i=0;
 
  while(i<10)
         {
              printf("%d \n",i);
               i++  ;
   }
}   

PROGRAM ON GOTO STATEMENT

#include <stdio.h>
 
void main()
{
   goto patna;
   
   begusrai:
   printf("hey i am in begusrai \n");
   
 
   goto deoghar;
   
   patna:
   printf("now u r in patna \n");
   
   goto begusrai;
   deoghar:
     printf("now u r in deoghar \n");
}

DO A LOOP WITOHOUT USING ANY LOOP

#include <stdio.h>
 
void main()
{
   int i=0;
   
   loop:
   if(i<10)
   
   {
   printf("%d \n",i);
    i++;
  }
   goto loop;
}

CALCULATE PRIME NUMBER

#include<stdio.h>
 
int main()
{
   int n, i = 3, count, c;
 
   printf("Enter the number of prime numbers required\n");
   scanf("%d",&n);
 
   if ( n >= 1 )
   {
      printf("First %d prime numbers are :\n",n);
      printf("2\n");
   }
 
   for ( count = 2 ; count <= n ;  )
   {
      for ( c = 2 ; c <= i - 1 ; c++ )
      {
         if ( i%c == 0 )
            break;
      }
      if ( c == i )
      {
         printf("%d\n",i);
         count++;
      }
      i++;
   }
 
   return 0;
}

CALCULATE FIBONACCI SERIES

#include<stdio.h>
 
int main()
{
   int n, first = 0, second = 1, next, c;
 
   printf("Enter the number of terms\n");
   scanf("%d",&n);
 
   printf("First %d terms of Fibonacci series are :-\n",n);
 
   for ( c = 0 ; c < n ; c++ )
   {
      if ( c <= 1 )
         next = c;
      else
      {
         next = first + second;
         first = second;
         second = next;
      }
      printf("%d\n",next);
   }
 
   return 0;
}

CHECK VOWEL

#include <stdio.h>
 
int main()
{
  char ch;
 
  printf("Enter a character\n");
  scanf("%c", &ch);
 
  if (ch == 'a' || ch == 'A' || ch == 'e' || ch == 'E' || ch == 'i' || ch == 'I' || ch =='o' || ch=='O' || ch == 'u' || ch == 'U')
    printf("%c is a vowel.\n", ch);
  else
    printf("%c is not a vowel.\n", ch);
 
  return 0;
}

LEAP YEAR

#include <stdio.h>
 
int main()
{
  int year;
 
  printf("Enter a year to check if it is a leap year\n");
  scanf("%d", &year);
 
  if ( year%400 == 0)
    printf("%d is a leap year.\n", year);
  else if ( year%100 == 0)
    printf("%d is not a leap year.\n", year);
  else if ( year%4 == 0 )
    printf("%d is a leap year.\n", year);
  else
    printf("%d is not a leap year.\n", year);  
 
  return 0;
}

CALCULATE FACTORIAL

#include <stdio.h>
 
int main()
{
  int c, n, fact = 1;
 
  printf("Enter a number to calculate it's factorial\n");
  scanf("%d", &n);
 
  for (c = 1; c <= n; c++)
    fact = fact * c;
 
  printf("Factorial of %d = %d\n", n, fact);
 
  return 0;
}

CALCULATE HCF AND LCM

#include <stdio.h>
 
int main() {
  int a, b, x, y, t, gcd, lcm;
 
  printf("Enter two integers\n");
  scanf("%d%d", &x, &y);
 
  a = x;
  b = y;
 
  while (b != 0) {
    t = b;
    b = a % b;
    a = t;
  }
 
  gcd = a;
  lcm = (x*y)/gcd;
 
  printf("Greatest common divisor of %d and %d = %d\n", x, y, gcd);
  printf("Least common multiple of %d and %d = %d\n", x, y, lcm);
 
  return 0;
}

DECIMAL TO BINARY CONVERSION

#include <stdio.h>
 
int main()
{
  int n, c, k;
 
  printf("Enter an integer in decimal number system\n");
  scanf("%d", &n);
 
  printf("%d in binary number system is:\n", n);
 
  for (c = 31; c >= 0; c--)
  {
    k = n >> c;
 
    if (k & 1)
      printf("1");
    else
      printf("0");
  }
 
  printf("\n");
 
  return 0;
}

Ncr and Npr

#include <stdio.h>
 
long factorial(int);
long find_ncr(int, int);
long find_npr(int, int);
 
int main()
{
   int n, r;
   long ncr, npr;
 
   printf("Enter the value of n and r\n");
   scanf("%d%d",&n,&r);
 
   ncr = find_ncr(n, r);
   npr = find_npr(n, r);
 
   printf("%dC%d = %ld\n", n, r, ncr);
   printf("%dP%d = %ld\n", n, r, npr);
 
   return 0;
}
 
long find_ncr(int n, int r) {
   long result;
 
   result = factorial(n)/(factorial(r)*factorial(n-r));
 
   return result;
}
 
long find_npr(int n, int r) {
   long result;
 
   result = factorial(n)/factorial(n-r);
 
   return result;
} 
 
long factorial(int n) {
   int c;
   long result = 1;
 
   for (c = 1; c <= n; c++)
      result = result*c;
 
   return result;
}

REVERSE NO

CALCULATE SIMPLE INTREST

#include <stdio.h>
 
int main()
{
   int n, reverse = 0;
 
   printf("Enter a number to reverse\n");
   scanf("%d", &n);
 
   while (n != 0)
   {
      reverse = reverse * 10;
      reverse = reverse + n%10;
      n       = n/10;
   }
 
   printf("Reverse of entered number is = %d\n", reverse);
 
   return 0;
}

CALCULATE PALINDROME NO

#include <stdio.h>
 
int main()
{
   int n, reverse = 0, temp;
 
   printf("Enter a number to check if it is a palindrome or not\n");
   scanf("%d",&n);
 
   temp = n;
 
   while( temp != 0 )
   {
      reverse = reverse * 10;
      reverse = reverse + temp%10;
      temp = temp/10;
   }
 
   if ( n == reverse )
      printf("%d is a palindrome number.\n", n);
   else
      printf("%d is not a palindrome number.\n", n);
 
   return 0;
}

PRINT A PYRAMIID

#include <stdio.h>
 
int main()
{
   int row, c, n, temp;
 
   printf("Enter the number of rows in pyramid of stars you wish to see ");
   scanf("%d",&n);
 
   temp = n;
 
   for ( row = 1 ; row <= n ; row++ )
   {
      for ( c = 1 ; c < temp ; c++ )
         printf(" ");
 
      temp--;
 
      for ( c = 1 ; c <= 2*row - 1 ; c++ )
         printf("*");
 
      printf("\n");
   }
 
   return 0;
}

PRINT A DIAMOND

#include <stdio.h>
 
int main()
{
  int n, c, k, space = 1;
 
  printf("Enter number of rows\n");
  scanf("%d", &n);
 
  space = n - 1;
 
  for (k = 1; k <= n; k++)
  {
    for (c = 1; c <= space; c++)
      printf(" ");
 
    space--;
 
    for (c = 1; c <= 2*k-1; c++)
      printf("*");
 
    printf("\n");
  }
 
  space = 1;
 
  for (k = 1; k <= n - 1; k++)
  {
    for (c = 1; c <= space; c++)
      printf(" ");
 
    space++;
 
    for (c = 1 ; c <= 2*(n-k)-1; c++)
      printf("*");
 
    printf("\n");
  }
 
  return 0;
}

CALCULATE ARMSTRONG NO

#include <stdio.h>
 
int power(int, int);
 
int main()
{
   int n, sum = 0, temp, remainder, digits = 0;
 
   printf("Input an integer\n");
   scanf("%d", &n);
 
   temp = n;
   // Count number of digits
   while (temp != 0) {
      digits++;
      temp = temp/10;
   }
 
   temp = n;
 
   while (temp != 0) {
      remainder = temp%10;
      sum = sum + power(remainder, digits);
      temp = temp/10;
   }
 
   if (n == sum)
      printf("%d is an Armstrong number.\n", n);
   else
      printf("%d is not an Armstrong number.\n", n);
 
   return 0;
}
 
int power(int n, int r) {
   int c, p = 1;
 
   for (c = 1; c <= r; c++) 
      p = p*n;
 
   return p;   
}

GENERATE ARMSTORNG NO

#include <stdio.h>
 
int check_armstrong(int);
int power(int, int);
 
int main () {
   int c, a, b;
 
   printf("Input two integers\n");
   scanf("%d%d", &a, &b);
 
   for (c = a; c <= b; c++) {
      if (check_armstrong(c) == 1)
         printf("%d\n", c);
   }
 
   return 0;
}
 
int check_armstrong(int n) {
   long long sum = 0, temp;
   int remainder, digits = 0;
 
   temp = n;
 
   while (temp != 0) {
      digits++;
      temp = temp/10;
   }
 
   temp = n;
 
   while (temp != 0) {
      remainder = temp%10;
      sum = sum + power(remainder, digits);
      temp = temp/10;
   }
 
   if (n == sum)
      return 1;
   else
      return 0;
}
 
int  power(int n, int r) {
   int c, p = 1;
 
   for (c = 1; c <= r; c++) 
      p = p*n;
 
   return p;   
}

PRINT FLOYD'S TRIANGLE

#include <stdio.h>
 
int main()
{
  int n, i,  c, a = 1;
 
  printf("Enter the number of rows of Floyd's triangle to print\n");
  scanf("%d", &n);
 
  for (i = 1; i <= n; i++)
  {
    for (c = 1; c <= i; c++)
    {
      printf("%d ",a);
      a++;
    }
    printf("\n");
  }
 
  return 0;
}

PRINT PASCAL TRIANGLE

#include <stdio.h>
 
long factorial(int);
 
int main()
{
   int i, n, c;
 
   printf("Enter the number of rows you wish to see in pascal triangle\n");
   scanf("%d",&n);
 
   for (i = 0; i < n; i++)
   {
      for (c = 0; c <= (n - i - 2); c++)
         printf(" ");
 
      for (c = 0 ; c <= i; c++)
         printf("%ld ",factorial(i)/(factorial(c)*factorial(i-c)));
 
      printf("\n");
   }
 
   return 0;
}
 
long factorial(int n)
{
   int c;
   long result = 1;
 
   for (c = 1; c <= n; c++)
         result = result*c;
 
   return result;
}

SUM OF NATURAL NO USING RECURSSION

#include <stdio.h>
int addNumbers(int n);

int main()
{
    int num;
    printf("Enter a positive integer: ");
    scanf("%d", &num);
    printf("Sum = %d",addNumbers(num));
    return 0;
}

int addNumbers(int n)
{
    if(n != 0)
        return n + addNumbers(n-1);
    else
        return n;
}

FACTORIAL OF A NO USING RECURSSION

#include <stdio.h>
long int multiplyNumbers(int n);

int main()
{
    int n;
    printf("Enter a positive integer: ");
    scanf("%d", &n);
    printf("Factorial of %d = %ld", n, multiplyNumbers(n));
    return 0;
}
long int multiplyNumbers(int n)
{
    if (n >= 1)
        return n*multiplyNumbers(n-1);
    else
        return 1;
}

GCD OF A NO USING RECURSSION

#include <stdio.h>
int hcf(int n1, int n2);
int main()
{
   int n1, n2;
   printf("Enter two positive integers: ");
   scanf("%d %d", &n1, &n2);

   printf("G.C.D of %d and %d is %d.", n1, n2, hcf(n1,n2));
   return 0;
}

int hcf(int n1, int n2)
{
    if (n2 != 0)
       return hcf(n2, n1%n2);
    else 
       return n1;
}

REVERSE A SENTENCE USING RECURSSION

POWER OF A NO USING RECURSSION

#include <stdio.h>

int power(int n1, int n2);

int main()
{
    int base, powerRaised, result;

    printf("Enter base number: ");
    scanf("%d",&base);

    printf("Enter power number(positive integer): ");
    scanf("%d",&powerRaised);

    result = power(base, powerRaised);

    printf("%d^%d = %d", base, powerRaised, result);
    return 0;
}

int power(int base, int powerRaised)
{
    if (powerRaised != 0)
        return (base*power(base, powerRaised-1));
    else
        return 1;
}

CONVERT NO TO DECIMAL AND VICE VERSA

#include <stdio.h>
#include <math.h>
int convertBinaryToDecimal(long long n);

int main()
{
    long long n;
    printf("Enter a binary number: ");
    scanf("%lld", &n);
    printf("%lld in binary = %d in decimal", n, convertBinaryToDecimal(n));
    return 0;
}

int convertBinaryToDecimal(long long n)
{
    int decimalNumber = 0, i = 0, remainder;
    while (n!=0)
    {
        remainder = n%10;
        n /= 10;
        decimalNumber += remainder*pow(2,i);
        ++i;
    }
    return decimalNumber;
}

CONVERT OCTAL TO DECIMAL AND VICE VERSA

#include <stdio.h>
#include <math.h>

int convertDecimalToOctal(int decimalNumber);
int main()
{
    int decimalNumber;

    printf("Enter a decimal number: ");
    scanf("%d", &decimalNumber);

    printf("%d in decimal = %d in octal", decimalNumber, convertDecimalToOctal(decimalNumber));

    return 0;
}

int convertDecimalToOctal(int decimalNumber)
{
    int octalNumber = 0, i = 1;

    while (decimalNumber != 0)
    {
        octalNumber += (decimalNumber % 8) * i;
        decimalNumber /= 8;
        i *= 10;
    }

    return octalNumber;
}

CONVERT BINARY NO TO OCTAL AND VICE VERSA

#include <stdio.h>
#include <math.h>

int convertBinarytoOctal(long long binaryNumber);
int main()
{
    long long binaryNumber;

    printf("Enter a binary number: ");
    scanf("%lld", &binaryNumber);

    printf("%lld in binary = %d in octal", binaryNumber, convertBinarytoOctal(binaryNumber));

    return 0;
}

int convertBinarytoOctal(long long binaryNumber)
{
    int octalNumber = 0, decimalNumber = 0, i = 0;

    while(binaryNumber != 0)
    {
        decimalNumber += (binaryNumber%10) * pow(2,i);
        ++i;
        binaryNumber/=10;
    }

    i = 1;

    while (decimalNumber != 0)
    {
        octalNumber += (decimalNumber % 8) * i;
        decimalNumber /= 8;
        i *= 10;
    }

    return octalNumber;
}

PROGRAM ON REFERENCE AND DEREFERENCE POINTER

#include <stdio.h>
int main(){
   int* pc;
   int c;
   c=22;
   printf("Address of c:%u\n",&c);
   printf("Value of c:%d\n\n",c);
   pc=&c;
   printf("Address of pointer pc:%u\n",pc);
   printf("Content of pointer pc:%d\n\n",*pc);
   c=11;
   printf("Address of pointer pc:%u\n",pc);
   printf("Content of pointer pc:%d\n\n",*pc);
   *pc=2;
   printf("Address of c:%u\n",&c);
   printf("Value of c:%d\n\n",c);
   return 0;
}

#include <stdio.h>
int main(){
   int* pc;
   int c;
   c=22;
   printf("Address of c:%u\n",&c);
   printf("Value of c:%d\n\n",c);
   pc=&c;
   printf("Address of pointer pc:%u\n",pc);
   printf("Content of pointer pc:%d\n\n",*pc);
   c=11;
   printf("Address of pointer pc:%u\n",pc);
   printf("Content of pointer pc:%d\n\n",*pc);
   *pc=2;
   printf("Address of c:%u\n",&c);
   printf("Value of c:%d\n\n",c);
   return 0;
}

#include <stdio.h>
int main(){
   int* pc;
   int c;
   c=22;
   printf("Address of c:%u\n",&c);
   printf("Value of c:%d\n\n",c);
   pc=&c;
   printf("Address of pointer pc:%u\n",pc);
   printf("Content of pointer pc:%d\n\n",*pc);
   c=11;
   printf("Address of pointer pc:%u\n",pc);
   printf("Content of pointer pc:%d\n\n",*pc);
   *pc=2;
   printf("Address of c:%u\n",&c);
   printf("Value of c:%d\n\n",c);
   return 0;
}

STORE INFORMATION (NAME,ROLL,MARKS) OF A STUDENT USING STRUCTURE

#include <stdio.h>
struct student
{
    char name[50];
    int roll;
    float marks;
} s;

int main()
{
    printf("Enter information:\n");

    printf("Enter name: ");
    scanf("%s", s.name);

    printf("Enter roll number: ");
    scanf("%d", &s.roll);

    printf("Enter marks: ");
    scanf("%f", &s.marks);


    printf("Displaying Information:\n");

    printf("Name: ");
    puts(s.name);

    printf("Roll number: %d\n",s.roll);

    printf("Marks: %.1f\n", s.marks);

    return 0;
}

STORE INFORMATION OF 10 STUDENT USING STRUCTURE

#include <stdio.h>
struct student
{
    char name[50];
    int roll;
    float marks;
} s[10];

int main()
{
    int i;

    printf("Enter information of students:\n");

    // storing information
    for(i=0; i<10; ++i)
    {
        s[i].roll = i+1;

        printf("\nFor roll number%d,\n",s[i].roll);

        printf("Enter name: ");
        scanf("%s",s[i].name);

        printf("Enter marks: ");
        scanf("%f",&s[i].marks);

        printf("\n");
    }

    printf("Displaying Information:\n\n");
    // displaying information
    for(i=0; i<10; ++i)
    {
        printf("\nRoll number: %d\n",i+1);
        printf("Name: ");
        puts(s[i].name);
        printf("Marks: %.1f",s[i].marks);
        printf("\n");
    }
    return 0;
}

STORE INFORMATION USING STRUCTURE FOR N ELEMENTS DYNAMICALLY

#include <stdio.h>
#include<stdlib.h>

struct course
{
   int marks;
   char subject[30];
};

int main()
{
   struct course *ptr;
   int i, noOfRecords;
   printf("Enter number of records: ");
   scanf("%d", &noOfRecords);

   // Allocates the memory for noOfRecords structures with pointer ptr pointing to the base address.
   ptr = (struct course*) malloc (noOfRecords * sizeof(struct course));

   for(i = 0; i < noOfRecords; ++i)
   {
       printf("Enter name of the subject and marks respectively:\n");
       scanf("%s %d", &(ptr+i)->subject, &(ptr+i)->marks);
   }

   printf("Displaying Information:\n");

   for(i = 0; i < noOfRecords ; ++i)
       printf("%s\t%d\n", (ptr+i)->subject, (ptr+i)->marks);

   return 0;
}

ADDITION USING POINTERS

#include <stdio.h>
 
int main()
{
   int first, second, *p, *q, sum;
 
   printf("Enter two integers to add\n");
   scanf("%d%d", &first, &second);
 
   p = &first;
   q = &second;
 
   sum = *p + *q;
 
   printf("Sum of entered numbers = %d\n",sum);
 
   return 0;
}

MAXIMUM AND MINIMUM ELEMENT IN ARRAY

#include <stdio.h>
 
int main()
{
  int array[100], maximum, size, c, location = 1;
 
  printf("Enter the number of elements in array\n");
  scanf("%d", &size);
 
  printf("Enter %d integers\n", size);
 
  for (c = 0; c < size; c++)
    scanf("%d", &array[c]);
 
  maximum = array[0];
 
  for (c = 1; c < size; c++)
  {
    if (array[c] > maximum)
    {
       maximum  = array[c];
       location = c+1;
    }
  }
 
  printf("Maximum element is present at location %d and it's value is %d.\n", location, maximum);
  return 0;
}

MINIMUM ELEMENT IN ARRAY

#include <stdio.h>
 
int main() 
{
    int array[100], minimum, size, c, location = 1;
 
    printf("Enter the number of elements in array\n");
    scanf("%d",&size);
 
    printf("Enter %d integers\n", size);
 
    for ( c = 0 ; c < size ; c++ )
        scanf("%d", &array[c]);
 
    minimum = array[0];
 
    for ( c = 1 ; c < size ; c++ ) 
    {
        if ( array[c] < minimum ) 
        {
           minimum = array[c];
           location = c+1;
        }
    } 
 
    printf("Minimum element is present at location %d and it's value is %d.\n", location, minimum);
    return 0;
}

LINEAR SEARCH

#include <stdio.h>
 
int main()
{
   int array[100], search, c, n;
 
   printf("Enter the number of elements in array\n");
   scanf("%d",&n);
 
   printf("Enter %d integer(s)\n", n);
 
   for (c = 0; c < n; c++)
      scanf("%d", &array[c]);
 
   printf("Enter the number to search\n");
   scanf("%d", &search);
 
   for (c = 0; c < n; c++)
   {
      if (array[c] == search)     /* if required element found */
      {
         printf("%d is present at location %d.\n", search, c+1);
         break;
      }
   }
   if (c == n)
      printf("%d is not present in array.\n", search);
 
   return 0;
}

BINARY SEARCH

#include <stdio.h>
 
int main()
{
   int c, first, last, middle, n, search, array[100];
 
   printf("Enter number of elements\n");
   scanf("%d",&n);
 
   printf("Enter %d integers\n", n);
 
   for (c = 0; c < n; c++)
      scanf("%d",&array[c]);
 
   printf("Enter value to find\n");
   scanf("%d", &search);
 
   first = 0;
   last = n - 1;
   middle = (first+last)/2;
 
   while (first <= last) {
      if (array[middle] < search)
         first = middle + 1;    
      else if (array[middle] == search) {
         printf("%d found at location %d.\n", search, middle+1);
         break;
      }
      else
         last = middle - 1;
 
      middle = (first + last)/2;
   }
   if (first > last)
      printf("Not found! %d is not present in the list.\n", search);
 
   return 0;   
}

REVERSE ARRAY

#include <stdio.h>
 
int main()
{
   int n, c, d, a[100], b[100];
 
   printf("Enter the number of elements in array\n");
   scanf("%d", &n);
 
   printf("Enter the array elements\n");
 
   for (c = 0; c < n ; c++)
      scanf("%d", &a[c]);
 
   /*
    * Copying elements into array b starting from end of array a
    */
 
   for (c = n - 1, d = 0; c >= 0; c--, d++)
      b[d] = a[c];
 
   /*
    * Copying reversed array into original.
    * Here we are modifying original array, this is optional.
    */
 
   for (c = 0; c < n; c++)
      a[c] = b[c];
 
   printf("Reverse array is\n");
 
   for (c = 0; c < n; c++)
      printf("%d\n", a[c]);
 
   return 0;
}

INSERT ELEMENT IN ARRAY

#include <stdio.h>
 
int main()
{
   int array[100], position, c, n, value;
 
   printf("Enter number of elements in array\n");
   scanf("%d", &n);
 
   printf("Enter %d elements\n", n);
 
   for (c = 0; c < n; c++)
      scanf("%d", &array[c]);
 
   printf("Enter the location where you wish to insert an element\n");
   scanf("%d", &position);
 
   printf("Enter the value to insert\n");
   scanf("%d", &value);
 
   for (c = n - 1; c >= position - 1; c--)
      array[c+1] = array[c];
 
   array[position-1] = value;
 
   printf("Resultant array is\n");
 
   for (c = 0; c <= n; c++)
      printf("%d\n", array[c]);
 
   return 0;
}

DELETE ELEMENT FROM ARRAY

#include <stdio.h>
 
int main()
{
   int array[100], position, c, n;
 
   printf("Enter number of elements in array\n");
   scanf("%d", &n);
 
   printf("Enter %d elements\n", n);
 
   for ( c = 0 ; c < n ; c++ )
      scanf("%d", &array[c]);
 
   printf("Enter the location where you wish to delete element\n");
   scanf("%d", &position);
 
   if ( position >= n+1 )
      printf("Deletion not possible.\n");
   else
   {
      for ( c = position - 1 ; c < n - 1 ; c++ )
         array[c] = array[c+1];
 
      printf("Resultant array is\n");
 
      for( c = 0 ; c < n - 1 ; c++ )
         printf("%d\n", array[c]);
   }
 
   return 0;
}

MERGE ARRAY

#include <stdio.h>
 
void merge(int [], int, int [], int, int []);
 
int main() {
  int a[100], b[100], m, n, c, sorted[200];
 
  printf("Input number of elements in first array\n");
  scanf("%d", &m);
 
  printf("Input %d integers\n", m);
  for (c = 0; c < m; c++) {
    scanf("%d", &a[c]);
  }
 
  printf("Input number of elements in second array\n");
  scanf("%d", &n);
 
  printf("Input %d integers\n", n);
  for (c = 0; c < n; c++) {
    scanf("%d", &b[c]);
  }
 
  merge(a, m, b, n, sorted);
 
  printf("Sorted array:\n");
 
  for (c = 0; c < m + n; c++) {
    printf("%d\n", sorted[c]);
  }
 
  return 0;
}
 
void merge(int a[], int m, int b[], int n, int sorted[]) {
  int i, j, k;
 
  j = k = 0;
 
  for (i = 0; i < m + n;) {
    if (j < m && k < n) {
      if (a[j] < b[k]) {
        sorted[i] = a[j];
        j++;
      }
      else {
        sorted[i] = b[k];
        k++;
      }
      i++;
    }
    else if (j == m) {
      for (; i < m + n;) {
        sorted[i] = b[k];
        k++;
        i++;
      }
    }
    else {
      for (; i < m + n;) {
        sorted[i] = a[j];
        j++;
        i++;
      }
    }
  }
}

BUBBLE SORT

#include <stdio.h>
 
int main()
{
  int array[100], n, c, d, swap;
 
  printf("Enter number of elements\n");
  scanf("%d", &n);
 
  printf("Enter %d integers\n", n);
 
  for (c = 0; c < n; c++)
    scanf("%d", &array[c]);
 
  for (c = 0 ; c < ( n - 1 ); c++)
  {
    for (d = 0 ; d < n - c - 1; d++)
    {
      if (array[d] > array[d+1]) /* For decreasing order use < */
      {
        swap       = array[d];
        array[d]   = array[d+1];
        array[d+1] = swap;
      }
    }
  }
 
  printf("Sorted list in ascending order:\n");
 
  for ( c = 0 ; c < n ; c++ )
     printf("%d\n", array[c]);
 
  return 0;
}

INSERTION SORT ASCENDING ORDER IN ARRAY

 
#include <stdio.h>
 
int main()
{
  int n, array[1000], c, d, t;
 
  printf("Enter number of elements\n");
  scanf("%d", &n);
 
  printf("Enter %d integers\n", n);
 
  for (c = 0; c < n; c++) {
    scanf("%d", &array[c]);
  }
 
  for (c = 1 ; c <= n - 1; c++) {
    d = c;
 
    while ( d > 0 && array[d] < array[d-1]) {
      t          = array[d];
      array[d]   = array[d-1];
      array[d-1] = t;
 
      d--;
    }
  }
 
  printf("Sorted list in ascending order:\n");
 
  for (c = 0; c <= n - 1; c++) {
    printf("%d\n", array[c]);
  }
 
  return 0;
}

SELECTION SORT USING ARRAY

#include <stdio.h>
 
int main()
{
   int array[100], n, c, d, position, swap;
 
   printf("Enter number of elements\n");
   scanf("%d", &n);
 
   printf("Enter %d integers\n", n);
 
   for ( c = 0 ; c < n ; c++ )
      scanf("%d", &array[c]);
 
   for ( c = 0 ; c < ( n - 1 ) ; c++ )
   {
      position = c;
 
      for ( d = c + 1 ; d < n ; d++ )
      {
         if ( array[position] > array[d] )
            position = d;
      }
      if ( position != c )
      {
         swap = array[c];
         array[c] = array[position];
         array[position] = swap;
      }
   }
 
   printf("Sorted list in ascending order:\n");
 
   for ( c = 0 ; c < n ; c++ )
      printf("%d\n", array[c]);
 
   return 0;
}

#include <stdio.h>
 
int main()
{
   int array[100], n, c, d, position, swap;
 
   printf("Enter number of elements\n");
   scanf("%d", &n);
 
   printf("Enter %d integers\n", n);
 
   for ( c = 0 ; c < n ; c++ )
      scanf("%d", &array[c]);
 
   for ( c = 0 ; c < ( n - 1 ) ; c++ )
   {
      position = c;
 
      for ( d = c + 1 ; d < n ; d++ )
      {
         if ( array[position] > array[d] )
            position = d;
      }
      if ( position != c )
      {
         swap = array[c];
         array[c] = array[position];
         array[position] = swap;
      }
   }
 
   printf("Sorted list in ascending order:\n");
 
   for ( c = 0 ; c < n ; c++ )
      printf("%d\n", array[c]);
 
   return 0;
}

PROGRAM TO ADD TWO MATRICES

#include <stdio.h>
 
int main()
{
   int m, n, c, d, first[10][10], second[10][10], sum[10][10];
 
   printf("Enter the number of rows and columns of matrix\n");
   scanf("%d%d", &m, &n);
   printf("Enter the elements of first matrix\n");
 
   for (c = 0; c < m; c++)
      for (d = 0; d < n; d++)
         scanf("%d", &first[c][d]);
 
   printf("Enter the elements of second matrix\n");
 
   for (c = 0; c < m; c++)
      for (d = 0 ; d < n; d++)
            scanf("%d", &second[c][d]);
 
   printf("Sum of entered matrices:-\n");
 
   for (c = 0; c < m; c++) {
      for (d = 0 ; d < n; d++) {
         sum[c][d] = first[c][d] + second[c][d];
         printf("%d\t", sum[c][d]);
      }
      printf("\n");
   }
 
   return 0;
}

PROGRAM TO SUBSTRACT MATRICES

#include <stdio.h>
 
int main()
{
   int m, n, c, d, first[10][10], second[10][10], difference[10][10];
 
   printf("Enter the number of rows and columns of matrix\n");
   scanf("%d%d", &m, &n);
   printf("Enter the elements of first matrix\n");
 
   for (c = 0; c < m; c++)
     for (d = 0 ; d < n; d++)
       scanf("%d", &first[c][d]);
 
   printf("Enter the elements of second matrix\n");
 
   for (c = 0; c < m; c++)
     for (d = 0; d < n; d++)
         scanf("%d", &second[c][d]);
 
   printf("Difference of entered matrices:-\n");
 
   for (c = 0; c < m; c++) {
     for (d = 0; d < n; d++) {
       difference[c][d] = first[c][d] - second[c][d];
       printf("%d\t",difference[c][d]);
     } 
     printf("\n");
   }
 
   return 0;
}

PROGRAM FOR TRANSPOSE MATRICES

#include <stdio.h>
 
int main()
{
   int m, n, c, d, matrix[10][10], transpose[10][10];
 
   printf("Enter the number of rows and columns of matrix\n");
   scanf("%d%d", &m, &n);
 
   printf("Enter the elements of matrix\n");
 
   for (c = 0; c < m; c++)
      for(d = 0; d < n; d++)
         scanf("%d",&matrix[c][d]);
 
   for (c = 0; c < m; c++)
      for( d = 0 ; d < n ; d++ )
         transpose[d][c] = matrix[c][d];
 
   printf("Transpose of entered matrix :-\n");
 
   for (c = 0; c < n; c++) {
      for (d = 0; d < m; d++)
         printf("%d\t",transpose[c][d]);
      printf("\n");
   }
 
   return 0;

MULTIPLY TWO MATRICES

#include <stdio.h>
 
int main()
{
  int m, n, p, q, c, d, k, sum = 0;
  int first[10][10], second[10][10], multiply[10][10];
 
  printf("Enter the number of rows and columns of first matrix\n");
  scanf("%d%d", &m, &n);
  printf("Enter the elements of first matrix\n");
 
  for (c = 0; c < m; c++)
    for (d = 0; d < n; d++)
      scanf("%d", &first[c][d]);
 
  printf("Enter the number of rows and columns of second matrix\n");
  scanf("%d%d", &p, &q);
 
  if (n != p)
    printf("Matrices with entered orders can't be multiplied with each other.\n");
  else
  {
    printf("Enter the elements of second matrix\n");
 
    for (c = 0; c < p; c++)
      for (d = 0; d < q; d++)
        scanf("%d", &second[c][d]);
 
    for (c = 0; c < m; c++) {
      for (d = 0; d < q; d++) {
        for (k = 0; k < p; k++) {
          sum = sum + first[c][k]*second[k][d];
        }
 
        multiply[c][d] = sum;
        sum = 0;
      }
    }
 
    printf("Product of entered matrices:-\n");
 
    for (c = 0; c < m; c++) {
      for (d = 0; d < q; d++)
        printf("%d\t", multiply[c][d]);
 
      printf("\n");
    }
  }
 
  return 0;
}

PRINT STRING USING INPUT

#include <stdio.h>
 
int main()
{
    char array[100];
 
    printf("Enter a string\n");
    scanf("%s", array);
 
    printf("You entered the string %s\n",array);
    return 0;
}

PROGRAM TO CALCULATE STRING LENGTH

#include <stdio.h>
#include <string.h>
 
int main()
{
   char a[100];
   int length;
 
   printf("Enter a string to calculate it's length\n");
   gets(a);
 
   length = strlen(a);
 
   printf("Length of entered string is = %d\n",length);
 
   return 0;
}

PROGRAM TO COMPARE TWO STRING USING STRCMP

include <stdio.h>
#include <string.h>
 
int main()
{
   char a[100], b[100];
 
   printf("Enter the first string\n");
   gets(a);
 
   printf("Enter the second string\n");
   gets(b);
 
   if (strcmp(a,b) == 0)
      printf("Entered strings are equal.\n");
   else
      printf("Entered strings are not equal.\n");
 
   return 0;
}

PROGRAM TO COPY A STRING

#include <stdio.h>
#include <string.h>
 
int main()
{
   char source[1000], destination[1000];
 
   printf("Input a string\n");
   gets(source);
 
   strcpy(destination, source);
 
   printf("Source string:      \"%s\"\n", source);
   printf("Destination string: \"%s\"\n", destination);
 
   return 0;
}

STRING CONCATENATION

#include <stdio.h>
#include <string.h>
 
int main()
{
   char a[1000], b[1000];
 
   printf("Enter the first string\n");
   gets(a);
 
   printf("Enter the second string\n");
   gets(b);
 
   strcat(a,b);
 
   printf("String obtained on concatenation is %s\n",a);
 
   return 0;
}

REVERSE A STRING

#include <stdio.h>
#include <string.h>
 
int main()
{
   char arr[100];
 
   printf("Enter a string to reverse\n");
   gets(arr);
 
   strrev(arr);
 
   printf("Reverse of entered string is \n%s\n",arr);
 
   return 0;
}

PROGRAM FOR PALINDROME NO

ADDITION USING POINTERS

#include <stdio.h>
#include <string.h>
 
int main()
{
   char a[100], b[100];
 
   printf("Enter the string to check if it is a palindrome\n");
   gets(a);
 
   strcpy(b,a);
   strrev(b);
 
   if (strcmp(a,b) == 0)
      printf("Entered string is a palindrome.\n");
   else
      printf("Entered string is not a palindrome.\n");
 
   return 0;
}

PROGRAM TO CONVERT STRING TO INTEGER

#include <stdio.h>
 
int toString(char []);
 
int main()
{
  char a[100];
  int n;
 
  printf("Input a valid string to convert to integer\n");
  scanf("%s", a);
 
  n = toString(a);
 
  printf("String  = %s\nInteger = %d\n", a, n);
 
  return 0;
}
 
int toString(char a[]) {
  int c, sign, offset, n;
 
  if (a[0] == '-') {  // Handle negative integers
    sign = -1;
  }
 
  if (sign == -1) {  // Set starting position to convert
    offset = 1;
  }
  else {
    offset = 0;
  }
 
  n = 0;
 
  for (c = offset; a[c] != '\0'; c++) {
    n = n * 10 + a[c] - '0';
  }
 
  if (sign == -1) {
    n = -n;
  }
 
  return n;
}

DELETE VOWELS

#include <stdio.h>
#include <string.h>
 
int check_vowel(char);
 
int main()
{
  char s[100], t[100];
  int i, j = 0;
 
  printf("Enter a string to delete vowels\n");
  gets(s);
 
  for(i = 0; s[i] != '\0'; i++) {
    if(check_vowel(s[i]) == 0) {       //not a vowel
      t[j] = s[i];
      j++;
    }
  }
 
  t[j] = '\0';
 
  strcpy(s, t);    //We are changing initial string
 
  printf("String after deleting vowels: %s\n", s);
 
  return 0;
}
 
 
int check_vowel(char c)
{
  switch(c) {
    case 'a':
    case 'A':
    case 'e':
    case 'E':
    case 'i':
    case 'I':
    case 'o':
    case 'O':
    case 'u':
    case 'U':
      return 1;
    default:
      return 0;
  }
}

PROGRAM FOR C SUB STRING

#include <stdio.h>
 
int main() 
{
   char string[1000], sub[1000];
   int position, length, c = 0;
 
   printf("Input a string\n");
   gets(string);
 
   printf("Enter the position and length of substring\n");
   scanf("%d%d", &position, &length);
 
   while (c < length) {
      sub[c] = string[position+c-1];
      c++;
   }
   sub[c] = '\0';
 
   printf("Required substring is \"%s\"\n", sub);
 
   return 0;
}

PROGRAM TO CHECK SUBSEQUENCE

#include <stdio.h>
#include <string.h>
 
int check_subsequence (char [], char[]);
 
int main () {
   int flag;
   char s1[1000], s2[1000];
 
   printf("Input first string\n");
   gets(s1);
 
   printf("Input second string\n");
   gets(s2);
 
   /** Passing smaller length string first */
 
   if (strlen(s1) < strlen(s2))
      flag = check_subsequence(s1, s2);
   else
      flag = check_subsequence(s2, s1);
 
   if (flag)
      printf("YES\n");
   else
      printf("NO\n");
 
   return 0;
}
 
int check_subsequence (char a[], char b[]) {
   int c, d;
 
   c = d = 0;
 
   while (a[c] != '\0') {
      while ((a[c] != b[d]) && b[d] != '\0') {
         d++;
      }
      if (b[d] == '\0')
         break;
      d++;
      c++;
   }
   if (a[c] == '\0')
      return 1;
   else
      return 0;
}

SORT STRING IN ALPHABETICAL ORDER

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
int main()
{
   char ch, input[100], output[100];
   int no[26] = {0}, n, c, t, x;
 
   printf("Enter some text\n");
   scanf("%s", input);
 
   n = strlen(input);
 
   /** Store how many times characters (a to z) 
      appears in input string in array */
 
   for (c = 0; c < n; c++)
   {
      ch = input[c] - 'a';
      no[ch]++;
   }
 
   t = 0;
 
   /** Insert characters a to z in output string 
       that many number of times as they appear 
       in input string */
 
   for (ch = 'a'; ch <= 'z'; ch++)
   {
      x = ch - 'a';
 
      for (c = 0; c < no[x]; c++)
      {
         output[t] = ch;
         t++;
      }
   }
   output[t] = '\0';
 
   printf("%s\n", output);
 
   return 0;
}

REMOVES SPACES,BLANKS FROM A STRING

#include <stdio.h>
 
int main()
{
   char text[1000], blank[1000];
   int c = 0, d = 0;
 
   printf("Enter some text\n");
   gets(text);
 
   while (text[c] != '\0') {
      if (text[c] == ' ') {
         int temp = c + 1;
         if (text[temp] != '\0') {
            while (text[temp] == ' ' && text[temp] != '\0') {
               if (text[temp] == ' ') {
                  c++;
               }  
               temp++;
            }
         }
      }
      blank[d] = text[c];
      c++;
      d++;
   }
 
   blank[d] = '\0';
 
   printf("Text after removing blanks\n%s\n", blank);
 
   return 0;
}

CONVERT TO LOWER CASE

#include <stdio.h>
#include <string.h>
 
int main()
{
   char string[1000];
 
   printf("Input a string to convert to lower case\n");
   gets(string);
 
   printf("Input string in lower case: \"%s\"\n",strlwr(string));
 
   return  0;
}

CONVERT TO UPPER CASE

#include <stdio.h>
#include <string.h>
 
int main()
{
   char string[1000];
 
   printf("Input a string to convert to upper case\n");
   gets(string);
 
   printf("Input string in upper case: \"%s\"\n",strupr(string));
 
   return  0;
}

CHANGE STRING USING STRUPR

#include <stdio.h>
 
void upper_string(char []);
 
int main()
{
   char string[100];
 
   printf("Enter a string to convert it into upper case\n");
   gets(string);
 
   upper_string(string);
 
   printf("Entered string in upper case is \"%s\"\n", string);
 
   return 0;
}
 
void upper_string(char s[]) {
   int c = 0;
 
   while (s[c] != '\0') {
      if (s[c] >= 'a' && s[c] <= 'z') {
         s[c] = s[c] - 32;
      }
      c++;
   }
}

CHANGE STRING TO LOWER CASE WITHOUT USING STRLWR

#include <stdio.h>
 
void lower_string(char []);
 
int main()
{
   char string[100];
 
   printf("Enter a string to convert it into lower case\n");
   gets(string);
 
   lower_string(string);
 
   printf("Entered string in lower case is \"%s\"\n", string);
 
   return 0;
}
 
void lower_string(char s[]) {
   int c = 0;
 
   while (s[c] != '\0') {
      if (s[c] >= 'A' && s[c] <= 'Z') {
         s[c] = s[c] + 32;
      }
      c++;
   }
}

FREQUECNY OF CHARACTER IN A STRING

#include <stdio.h>
#include <string.h>
 
int main()
{
   char string[100];
   int c = 0, count[26] = {0};
 
   printf("Enter a string\n");
   gets(string);
 
   while (string[c] != '\0')
   {
      /** Considering characters from 'a' to 'z' only
          and ignoring others */
 
      if (string[c] >= 'a' && string[c] <= 'z') 
         count[string[c]-'a']++;
 
      c++;
   }
 
   for (c = 0; c < 26; c++)
   {
      /** Printing only those characters 
          whose count is at least 1 */
 
      if (count[c] != 0)
         printf("%c occurs %d times in the entered string.\n",c+'a',count[c]);
   }
 
   return 0;
}

ANAGRAM PROGRAM IN C

#include <stdio.h>
 
int check_anagram(char [], char []);
 
int main()
{
   char a[100], b[100];
   int flag;
 
   printf("Enter first string\n");
   gets(a);
 
   printf("Enter second string\n");
   gets(b);
 
   flag = check_anagram(a, b);
 
   if (flag == 1)
      printf("\"%s\" and \"%s\" are anagrams.\n", a, b);
   else
      printf("\"%s\" and \"%s\" are not anagrams.\n", a, b);
 
   return 0;
}
 
int check_anagram(char a[], char b[])
{
   int first[26] = {0}, second[26] = {0}, c = 0;
 
   while (a[c] != '\0')
   {
      first[a[c]-'a']++;
      c++;
   }
 
   c = 0;
 
   while (b[c] != '\0')
   {
      second[b[c]-'a']++;
      c++;
   }
 
   for (c = 0; c < 26; c++)
   {
      if (first[c] != second[c])
         return 0;
   }
 
   return 1;
}

C PROGRAM TO OPEN A FILE

#include <stdio.h>
#include <stdlib.h>
 
int main()
{
   char ch, file_name[25];
   FILE *fp;
 
   printf("Enter the name of file you wish to see\n");
   gets(file_name);
 
   fp = fopen(file_name,"r"); // read mode
 
   if( fp == NULL )
   {
      perror("Error while opening the file.\n");
      exit(EXIT_FAILURE);
   }
 
   printf("The contents of %s file are :\n", file_name);
 
   while( ( ch = fgetc(fp) ) != EOF )
      printf("%c",ch);
 
   fclose(fp);
   return 0;
}

COPY FILES

#include <stdio.h>
#include <stdlib.h>
 
int main()
{
   char ch, source_file[20], target_file[20];
   FILE *source, *target;
 
   printf("Enter name of file to copy\n");
   gets(source_file);
 
   source = fopen(source_file, "r");
 
   if( source == NULL )
   {
      printf("Press any key to exit...\n");
      exit(EXIT_FAILURE);
   }
 
   printf("Enter name of target file\n");
   gets(target_file);
 
   target = fopen(target_file, "w");
 
   if( target == NULL )
   {
      fclose(source);
      printf("Press any key to exit...\n");
      exit(EXIT_FAILURE);
   }
 
   while( ( ch = fgetc(source) ) != EOF )
      fputc(ch, target);
 
   printf("File copied successfully.\n");
 
   fclose(source);
   fclose(target);
 
   return 0;
}

MERGE TWO FILES

#include <stdio.h>
#include <stdlib.h>
 
int main()
{
   FILE *fs1, *fs2, *ft;
 
   char ch, file1[20], file2[20], file3[20];
 
   printf("Enter name of first file\n");
   gets(file1);
 
   printf("Enter name of second file\n");
   gets(file2);
 
   printf("Enter name of file which will store contents of two files\n");
   gets(file3);
 
   fs1 = fopen(file1,"r");
   fs2 = fopen(file2,"r");
 
   if( fs1 == NULL || fs2 == NULL )
   {
      perror("Error ");
      printf("Press any key to exit...\n");
      getch();
      exit(EXIT_FAILURE);
   }
 
   ft = fopen(file3,"w");
 
   if( ft == NULL )
   {
      perror("Error ");
      printf("Press any key to exit...\n");
      exit(EXIT_FAILURE);
   }
 
   while( ( ch = fgetc(fs1) ) != EOF )
      fputc(ch,ft);
 
   while( ( ch = fgetc(fs2) ) != EOF )
      fputc(ch,ft);
 
   printf("Two files were merged into %s file successfully.\n",file3);
 
   fclose(fs1);
   fclose(fs2);
   fclose(ft);
 
   return 0;
}

C PROGRAM TO DELETE A FILE

#include<stdio.h>
 
main()
{
   int status;
   char file_name[25];
 
   printf("Enter the name of file you wish to delete\n");
   gets(file_name);
 
   status = remove(file_name);
 
   if( status == 0 )
      printf("%s file deleted successfully.\n",file_name);
   else
   {
      printf("Unable to delete the file\n");
      perror("Error");
   }
 
   return 0;
}

C PROGRAM TO GENERATE RANDOM NO

#include <stdio.h>
#include <stdlib.h>
 
int main() {
  int c, n;
 
  printf("Ten random numbers in [1,100]\n");
 
  for (c = 1; c <= 10; c++) {
    n = rand() % 100 + 1;
    printf("%d\n", n);
  }
 
  return 0;
}

PROGRAM TO ADD COMPLEX NO

#include <stdio.h>
 
struct complex
{
   int real, img;
};
 
int main()
{
   struct complex a, b, c;
 
   printf("Enter a and b where a + ib is the first complex number.\n");
   printf("a = ");
   scanf("%d", &a.real);
   printf("b = ");
   scanf("%d", &a.img);
   printf("Enter c and d where c + id is the second complex number.\n");
   printf("c = ");
   scanf("%d", &b.real);
   printf("d = ");
   scanf("%d", &b.img);
 
   c.real = a.real + b.real;
   c.img = a.img + b.img;
 
   if ( c.img >= 0 )
      printf("Sum of two complex numbers = %d + %di\n", c.real, c.img);
   else
      printf("Sum of two complex numbers = %d %di\n", c.real, c.img);
 
   return 0;
}

C PROGRAM TO WRITE A SENTENCE TO A FILE

#include <stdio.h>
#include <stdlib.h>  /* For exit() function */
int main()
{
   char sentence[1000];
   FILE *fptr;

   fptr = fopen("program.txt", "w");
   if(fptr == NULL)
   {
      printf("Error!");
      exit(1);
   }
   
   printf("Enter a sentence:\n");
   gets(sentence);

   fprintf(fptr,"%s", sentence);
   fclose(fptr);

   return 0;
}

PROGRAM USING MALLOC AND FREE FUNCTION

#include <stdio.h>
#include <stdlib.h>

int main()
{
    int num, i, *ptr, sum = 0;

    printf("Enter number of elements: ");
    scanf("%d", &num);

    ptr = (int*) malloc(num * sizeof(int));  //memory allocated using malloc
    if(ptr == NULL)                     
    {
        printf("Error! memory not allocated.");
        exit(0);
    }

    printf("Enter elements of array: ");
    for(i = 0; i < num; ++i)
    {
        scanf("%d", ptr + i);
        sum += *(ptr + i);
    }

    printf("Sum = %d", sum);
    free(ptr);
    return 0;
}

PROGRAM USING CALLOC AND FREE FUNCTION

#include <stdio.h>
#include <stdlib.h>

int main()
{
    int num, i, *ptr, sum = 0;
    printf("Enter number of elements: ");
    scanf("%d", &num);

    ptr = (int*) calloc(num, sizeof(int));
    if(ptr == NULL)
    {
        printf("Error! memory not allocated.");
        exit(0);
    }

    printf("Enter elements of array: ");
    for(i = 0; i < num; ++i)
    {
        scanf("%d", ptr + i);
        sum += *(ptr + i);
    }

    printf("Sum = %d", sum);
    free(ptr);
    return 0;
}

PROGRAM USING REALLOC FUNCTION

#include <stdio.h>
#include <stdlib.h>

int main()
{
    int *ptr, i , n1, n2;
    printf("Enter size of array: ");
    scanf("%d", &n1);

    ptr = (int*) malloc(n1 * sizeof(int));

    printf("Address of previously allocated memory: ");
    for(i = 0; i < n1; ++i)
         printf("%u\t",ptr + i);

    printf("\nEnter new size of array: ");
    scanf("%d", &n2);
    ptr = realloc(ptr, n2);
    for(i = 0; i < n2; ++i)
         printf("%u\t", ptr + i);
    return 0;
}

SHUTDOWN COMPUTER USING C PROGRAM

#include <stdio.h>
#include <stdlib.h>
 
int main()
{
   system("C:\\WINDOWS\\System32\\shutdown /s");
 
   return 0;
}