编辑代码

#include <iostream>
using namespace std;

int f(int length,int width)
{
    if(length<=0||width<=0)
    {
        cout<<"error!"<<endl;
        return -1;
    }
    
    if(length%width==0)
    return width;
    
    int smallwidth=length%width;
    return f(width,smallwidth);
}

int main() {
    cout<<"最小正方形的边长为："<<f(680,240);
	return 0;
}