#include<stdio.h>
#include<math.h>
int main()
{
    int num , rem=0 , sum=0 , original , n =0 ;

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

     original = num;

     while(original > 0)
    {
        original = original /10;
        ++n;
    }
    original = num ;

     while( original > 0)
    {
        rem = original % 10;
        sum = sum + pow(rem , n);
        original = original /10;
    }
    if(sum == num)
        printf(" %d is an armstrong number ", num);
    else
        printf(" %d is not an armstrong number ", num);

         return 0;
}

OUTPUT :

 Enter the number : 153
153 is an armstrong number

 Enter the number : 145
145 is not an armstrong number