check Armstrong number in the C program

#include<stdio.h>
#include<math.h>
#define pow
int main()
{
    int num,num1,num2,n,q,sum=0,no_of_digits=0;
    printf("enter  a number\n");
    scanf("%d",&num);
    num1=num2=num; //storing the entered number in another variable 'num1'
    while (num!=0) //calclating and storing the number of digits in 'digit'
    {
        num=num/10; //dividing the number by 10. int data type ignores the decimal value, giving an integer
        no_of_digits++; 
    }
    while (num1!=0) 
    {
        n=num1%10; //taking one digit at a time in n
        q=pow(n,no_of_digits);//each digit^no. of digits
        sum=sum+q; // sum of all digit^no. of digits
        num1=num1/10;
        
    }
     printf("Sum of each digit^no. of digits =%d\n",sum);
     if (sum==num2)
        printf("%d is an armstrong number\n",num2);
     else
        printf("%d is NOT an armstrong number\n",num2);

  return 0;
}