51Nod1011 最大公约数GCD

#include<iostream>
#include<string>
#include<cstring>
#include<cstdio>
using namespace std;
int gcd(int a,int b)
{
  if(a%b==0)
    return b;
  return gcd(b,a%b);
}
int main()
{
  int a,b;
  int i;
  cin>>a>>b;
  if(a<b)
    cout<<gcd(b,a);
  else 
    cout<<gcd(a,b);
  return 0;
}