#include <stdio.h>



int main(void){
  int m, n, r;
  printf("input 2 numbers(white space)\n");
  scanf("%d%d",&m,&n);
  if(n>m){
	r=m;
	m=n;
	n=r;
  }

  printf("m=%d",m);
  printf(" n=%d",n);

  r = m % n;

  while (r!=0) {
    m = n;
    n = r;
    r = m % n;
  }

  printf("\n greatest common measure = %d\n", n);

  return 0;
}