GCD求最大公约数

求最大公约数哪个强，果断GCD，非递归版本和递归版本如下：

#include<iostream>
using namespace std;

int gcd(int a, int b){ //非递归版本
  int big = max(a, b);
  int small = min(a, b);
  int temp;
  while(small != 0 ){
    temp = big % small;    
    big = small;
    small = temp;
  }
  return big;
}

int gcd_(int a, int b){//递归版本
  int big = max(a, b);
  int small = min(a, b);
  int temp = big % small;
  return temp == 0 ? small : gcd_(small, temp);
}

int main(){
  int a = 34, b = 8;
  cout<<gcd(a, b)<<endl;
  cout<<gcd_(a, b)<<endl;
  return 0;
}
//output:
// 2
// 2