#include <iostream>
using namespace std;
int divideToSquare(int length, int width) {
if (length < width||length<=0||width<=0)
{
cout<<"please check your input"<<endl;
}
if (length % width == 0) {
return width;
}
int smallWidth = length % width;
return divideToSquare(width, smallWidth);
}
int main() {
int length = 1680;
int width = 640;
cout<<"the width of square is"<<divideToSquare(length,width)<<endl;
return 0;
}