求两个数的最大公约数

用c++递归

#include <cstdio>#include <iostream>using namespace std;int gcd (int x, int y);int main (){    int a, b;    scanf ("%d %d",&a, &b);    printf ("%d", gcd(a, b));    return 0;}int gcd (int x, int y){    if (y==1)    {        printf ("none");        return 0;    }    if (y==0)        return x;    gcd (y, x%y);}