APIO 2011 - Find the Path

Code

1#include <bits/stdc++.h>
2#define FOR(i, x, y) for (int i = x; i < y; i++)
3typedef long long ll;
4using namespace std;
5
6struct Rect {
7    int x1, y1, x2, y2;
8    Rect(int a = 0, int b = 0, int c = 0, int d = 0): x1(a), y1(b), x2(c), y2(d) {
9        if (x1 > x2) swap(x1, x2);
10        if (y1 > y2) swap(y1, y2);