strong number between 1 to 10 in c program

#cprogram

In this article, we will see how you can calculate strong number from 1 to 10.
Strong number is a special number whose sum of the factorial of digits is equal to the original number

#include <stdio.h>

int factorial(int a);
int main() {
  int fact = 1, sum = 0;
  int n, r;
  n = 10;
  printf("Strong numbers are :");
  for (int i = 1; i <= n; i++) {
    int k = i;
    while (k != 0) {
      r = k % 10;
      fact = factorial(r);
      k = k / 10;
      sum = sum + fact;
    }
    if (sum == i) {
      printf("%d, ", i);
    }
    sum = 0;
  }
  return 0;
}
int factorial(int f) {
  int fact = 1;
  for (int i = 1; i <= f; i++) {
    fact = fact * i;
  }
  return fact;
}

output:
Strong numbers are :1, 2

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