Submission #684050

#	Time	Username	Problem	Language	Result	Execution time	Memory
684050		pragmatist	Marriage questions (IZhO14_marriage)	C++17	52 / 100	1588 ms	3192 KiB

marriage

/*
#pragma comment(linker, "/stack:200000000")
#pragma GCC optimize("O3")
#pragma GCC target ("avx2")
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize("unroll-loops")
*/

#include<bits/stdc++.h>
 
#define ld long double
#define sz(v) (int)v.size()
#define ll long long
#define pb push_back
#define x first
#define y second
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define nl "\n"

using namespace std;
using pii = pair<int, int>;

const int N = (int)3e4 + 7; // make sure this is right
const int M = (int)2e3 + 7;
const int inf = (int)2e9 + 7;
const ll INF = (ll)3e18 + 7; 
const double PI = acos(-1);
ll MOD = (ll)1e9 + 7; // make sure this is right

bool bit(int x, int i) {
	return x >> i & 1;
}

int sum(int x, int y) {
	x += y;
	if(x >= MOD) x -= MOD;
	return x;
}

pii dir[] = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}};

int n, m, k, mt[N + M];
int T, used[N], a[4 * N], b[4 * N];
vector<int> g[N];

bool dfs(int v) {
	if(used[v] == T) return 0;
	used[v] = T;
	for(auto to : g[v]) {
		if(mt[to] == -1) {
			mt[to] = v;
			return 1;
		}
	}
	for(auto to : g[v]) {
		if(dfs(mt[to])) {
			mt[to] = v;
			return 1;
		}
	}
	return 0;
}

void solve() {
	cin >> n >> m >> k;
	for(int i = 1; i <= k; ++i) {
		cin >> a[i] >> b[i];
	}
	int ans = 0;
	for(int l = 1; l <= n; ++l) {
		for(int r = l; r <= n; ++r) {
			for(int i = 1; i <= n; ++i) g[i].clear();
			for(int i = n + 1; i <= n + m; ++i) mt[i] = -1;
			for(int i = 1; i <= k; ++i) {
				if(a[i] >= l && a[i] <= r) {
					g[a[i]].pb(b[i] + n);
				}
			}
			for(int i = 1; i <= n; ++i) {
				T++;
				dfs(i);
			}
			bool ok = 1;
			for(int i = n + 1; i <= n + m && ok; ++i) ok &= (mt[i] != -1);
			if(ok) ans++;
		} 
	}
	cout << ans;
}

signed main() {	
	ios_base::sync_with_stdio(0);
	cin.tie(0);
//	freopen("g.in", "r", stdin);
//	freopen("g.out", "w", stdout);
	int test = 1;
	//cin >> test;
	for(int i = 1; i <= test; ++i) {
	 	//cout << "Case #" << i << ": ";
		solve();
	}
	return 0;
}

• Subtask 1: 52 / 100