ACM篇：UVa 839 -- Not so Mobile

#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <cstring>
#include <sstream>
#include <cmath>
using namespace std;

bool failed;

int _solve()
{
    int w1, d1, w2, d2;
    scanf("%d%d%d%d", &w1, &d1, &w2, &d2);
    if (!w1)
        w1 = _solve();
    if (!w2)
        w2 = _solve();
    if (w1 * d1 != w2 * d2)
        failed = true;
    return w1 + w2;
}
int main()
{
    int T;
    scanf("%d", &T);
    while (T-- > 0)
    {
        failed = false;
        _solve();
        printf("%s\n", (failed) ? "NO" : "YES");
        if (T)
            putchar('\n');
    }
    return 0;
}