itsa基 10 輾轉相除法

#include <iostream>
using namespace std;

int main ()
{
int a,b;
cin >> a >> b;

while (a != 0 && b != 0)
{
if (a >= b)
{
a = a % b;
}
else
{
b = b % a;
}
}
if (a >= b)
{
cout << a << endl;
}
else
{
cout << b << endl;
}
return 0;
}