while loop

           C programs based on while loop

Sample Program based on Looping concept

C program to print 1 to 10 numbers using for loop.

#include<stdio.h>

int main()

{

  int i;

  for(i=1; i<=10; i++)

  {

     printf("%d ", i);

  }

  return 0;

}

Output of program

1 2 3 4 5 6 7 8 9 10

1.C program to print A to Z using while loop.

#include<stdio.h>
int main()
{
  char ch='A';

  while(ch <= 'Z')
  {
printf("%c ", ch);
ch = ch + 1;
  }
  return 0;
}

Output of the program:

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

2.C program to print 10 to 20 numbers using while loop.

#include<stdio.h> 
int main()
{
int number=10;

while(number <= 20)
{
printf("%d ", number);
number = number + 1;
}
 return 0;
}

Output of the program: 

10 11 12 13 14 15 16 17 18 19 20

3.C program to count no. of digits in a given number.

#include <stdio.h> int main() {   int number, count=0;   printf("Enter your number: ");   scanf("%d", &number);   while(number!=0)   {       number = number / 10;          count = count + 1;   }   printf("Number of digits = %d", count);   return 0; }

Output of the program: 

Enter your number: 10123

Number of digits = 5

4.C program to calculate the power of an integer without use of inbuilt math function.

#include <stdio.h>

int main()
{

  int base, exponent, flag;

  long int answer=1;

 

  printf("Enter base number:");

  scanf("%d", &base);

 

  printf("Enter exponent number:");

  scanf("%d", &exponent);

  flag = exponent;

  while (flag != 0)

  {

      answer = answer * base; 

      --flag;

  }

  printf("Power of %d to the %d = %d", base, exponent, answer);

  return 0;
}

Output of the program: 

Enter base number:2

Enter exponent number:5

Power of 2 to the 5 = 32

5.C program to count words in a given string.

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

int main(){

char str1[80]="Hello Student How are you?", *token ;
const char s[2] = " ";
    
int counter=0;
printf("Given String = %s",str1);
token = strtok(str1,s);
while (token != NULL)
{
counter++;
token = strtok(NULL, s);
}
printf("\nTotal words in a given string is %d", counter );
 return 0;
}


Output of the program: 

Given String = Hello Student How are you?
Total words in a given string is 5

6..Greatest Common Divisor(GCD) of given 2 numbers

Write a C program to find Greatest Common Divisor (GCD) of given 2 numbers.

      GCD is also known as Greatest Common Factor (GCF)

      GCD is also known as Highest Common Factor (HCF)

#include <stdio.h>
int main()
{
  int num1, num2, i, j, temp, gcd;

  printf("Enter number 1:");
  scanf("%d", &i);

  printf("Enter number 2:");
  scanf("%d", &j);

  num1 = i;
  num2 = j;

  while (num2 != 0)
  {
    temp = num2;
    num2 = num1 % num2;
    num1 = temp;
  }

  gcd = num1;
  printf("Greatest Common Divisor(GCD) of %d and %d is %d.\n", i,j,gcd);
  return 0;
}

Output of  the program:

Enter number 1:20
Enter number 2:30
Greatest Common Divisor(GCD) of 20 and 30 is 10.