Submission #1204504

#	Time	Username	Problem	Language	Result	Execution time	Memory
1204504		countless	Rectangles (IOI19_rect)	C++20	18 / 100	5099 ms	332056 KiB

rect

#include "rect.h"
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;

const ll MOD = 998244353;
const ll INF = 1e18;
const ld EPS = 1e-12;

#define endl "\n"
#define sp <<" "<<
#define REP(i, a, b) for(ll i = a; i < b; i++)
#define dbg(x) cout << #x << " = " << x << endl
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define fast_io() ios_base::sync_with_stdio(false); cin.tie(NULL)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sz(x) ((ll)(x).size())

struct custom_hash {
	static uint64_t splitmix64(uint64_t x) {
		// http://xorshift.di.unimi.it/splitmix64.c
		x += 0x9e3779b97f4a7c15;
		x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
		x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
		return x ^ (x >> 31);
	}

	size_t operator()(uint64_t x) const {
		static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
		return splitmix64(x + FIXED_RANDOM);
	}
};

template <typename Key, typename Value>
using hash_map = unordered_map<Key, Value, custom_hash>;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
// uniform_int_distribution<int>(a, b)(rng);
// shuffle(all(a), rng);

// d, u, r, l
int dx[4] = {1, -1, 0, 0};
int dy[4] = {0, 0, 1, -1};

// giving up and turning in a brute force
ll count_rectangles(vector<vector<int>> a) {
	ll n = a.size(), m = a[0].size();
	ll ans = 0, curr;
	// assert(n <= 30 and m <= 30);
	
	auto in = [&](int x, int y) -> bool {
		return (0 < x and x < n-1 and 0 < y and y < m-1);
	};

	map<pair<pair<int, int>, pair<int, int>>, bool> vis;

	auto checkRect = [&](int x, int y, int xx, int yy) -> int {
		if (!in(x,y) or !in(xx, yy)) return 0;

		if (x > xx) swap(x, xx);
		if (y > yy) swap(y, yy);

		if (vis[{{x, y}, {xx, yy}}]) return 0;

		vis[{{x, y}, {xx, yy}}] = true;

		REP(i, x, xx+1) {
			REP(j, y, yy+1) {
				int val = a[i][j];

				if (val >= a[i][y-1] or val >= a[i][yy+1] or val >= a[x-1][j] or val >= a[xx+1][j]) {
					return 0;
				}
			}
		}

		return 1;
	};

	REP(i, 0, n*m) {
		int x = i / m, y = i % m;
		REP(j, i, n*m) {
			int xx = j / m, yy = j % m;
			ans += checkRect(x, y, xx, yy);
		}
	}

	return ans;
}

• Subtask 1: 8 / 8
• Subtask 2: 0 / 7
• Subtask 3: 0 / 12
• Subtask 4: 0 / 22
• Subtask 5: 10 / 10
• Subtask 6: 0 / 13
• Subtask 7: 0 / 28