#include <stdio.h>

int main(void) {
  int i, j, sml, lg, rem;
 
  printf("Enter two positive integers: ");
  scanf("%d %d", &i, &j);

  for(sml = i <= j ? i : j, lg = i<=j ? j : i;
      sml > 0;
      rem = lg % sml, lg = sml, sml = rem);

  printf("GCD of %d and %d is %d\n\n", i, j, lg);
  
  return 0;
}