while Loop in C Programming

Program 1

// Program for factorial of number
#include<stdio.h>
#include<conio.h>
int main()
{
    system("cls");
     int n,f=1,m;
     printf("Enter a number");
     scanf("%d",&n);
     m=n;
     while(n!=0)
     {
        f=f*n;
        n--;
     }
    printf("Factorial of %d  is %d ",m,f);
   return 0;
}

Program 2

// Program for addition of individual digits
#include<stdio.h>
#include<conio.h>
int main()
{
    system("cls");
      int n,r,s=0;
      printf("Enter a number");
      scanf("%d",&n);
      while(n!=0)
      {
          r=n%10;
          s=s+r;
          n=n/10;
      }
      printf("Addition is %d: ",s);
      return 0;
}  

Program 3

// Program for reverse of number
#include<stdio.h>
#include<conio.h>
int main()
{
    system("cls");
      int n,r,s=0,m;
      printf("Enter a number");
      scanf("%d",&n);
      m=n;
      while(n!=0)
      {
          r=n%10;
          s=s*10+r;
          n=n/10;
      }
      printf("Reverse of %d is %d ",m,s);
      return 0;
}  

Program 4

// Program for palindrom number
#include<stdio.h>
#include<conio.h>
int main()
{
    system("cls");
      int n,r,s=0,m;
      printf("Enter a number");
      scanf("%d",&n);
      m=n;
      while(n!=0)
      {
          r=n%10;
          s=s*10+r;
          n=n/10;
      }
      if(m==s)
        printf("No is Palimdrom");
      else
         printf("No is not Palimdrom"); 
      return 0;
}  

Program 5

// Program for armstrong number
#include<stdio.h>
#include<conio.h>
int main()
{
      system("cls");
      int n,r,s=0,m;
      printf("Enter a number");
      scanf("%d",&n);
      m=n;
      while(n!=0)
      {
          r=n%10;
          s=s+(r*r*r);
          n=n/10;
      }
      if(m==s)
        printf("No is Armstrong");
      else
         printf("No is not Armstrong"); 
      return 0;
}