Submission #144325

#	Time	Username	Problem	Language	Result	Execution time	Memory
144325		Minnakhmetov	Seats (IOI18_seats)	C++14	37 / 100	4100 ms	127324 KiB

seats

#include "seats.h"
#include<bits/stdc++.h>

using namespace std;

const int N = 1e6 + 5, INF = 1e9, G = 5;
int n, m, len;
vector<int> x, y;
vector<vector<int>> num;
int dx[4] = { 0, 0, 1, 1 }, dy[4] = { 1, 0, 0, 1};

struct Node {
	int mn, ct, up;
} t[N * 4];

Node operator + (Node a, Node b) {
	if (a.mn == b.mn) {
		a.ct += b.ct;
		return a;
	}
	if (a.mn < b.mn)
		return a;
	return b;
}

void push(int v, int L, int R) {
	if (t[v].up) {
		if (L != R) {
			t[v * 2].up += t[v].up;
			t[v * 2 + 1].up += t[v].up;
		}
		t[v].mn += t[v].up;
		t[v].up = 0;
	}
}

void upd(int l, int r, int x, int v, int L, int R) {
	push(v, L, R);
	if (l > r)
		return;
	if (l == L && r == R) {
		t[v].up += x;
		push(v, L, R);
	}
	else {
		int m = (L + R) >> 1;
		upd(l, min(m, r), x, v * 2, L, m);
		upd(max(m + 1, l), r, x, v * 2 + 1, m + 1, R);
		t[v] = t[v * 2] + t[v * 2 + 1];
	}
}

void upd2times2(int a, int b, int d) {
	vector<pair<int, int>> v;
	for (int j = 0; j < 4; j++) {
		v.push_back({ a + dx[j], b + dy[j] });
	}	

	sort(v.begin(), v.end(), [&](pair<int, int> p, pair<int, int> q) {
		return num[p.first][p.second] < num[q.first][q.second];
	});

	if (num[v[0].first][v[0].second] != INF)
		upd(num[v[0].first][v[0].second], min(len - 1, num[v[1].first][v[1].second] - 1), d, 1, 0, len - 1);

	if (num[v[2].first][v[2].second] != INF)
		upd(num[v[2].first][v[2].second], min(len - 1, num[v[3].first][v[3].second] - 1), d * G, 1, 0, len - 1);
}

void change(int a, int b, int d) {
	for (int i = 0; i < 4; i++) {
		upd2times2(a - dx[i], b - dy[i], d);
	}
}

// void que(int v, int L, int R) {
// 	push(v, L, R);
// 	if (L == R) {
// 		cout << t[v].mn << " ";
// 	}
// 	else {
// 		int m = (L + R) >> 1;
// 		que(v * 2, L, m);
// 		que(v * 2 + 1, m + 1, R);
// 	}
// }

void give_initial_chart(int H, int W, std::vector<int> R, std::vector<int> C) {
	n = H;
	m = W;
	x = R;
	y = C;

	len = n * m;

	num.resize(n + 2, vector<int>(m + 2, INF));

	fill(t, t + len * 4, (Node){0, 1, 0});

	for (int i = 0; i < len; i++) {
		x[i]++;
		y[i]++;
		num[x[i]][y[i]] = i;
	}

	for (int i = 0; i <= n; i++) {
		for (int j = 0; j <= m; j++) {
			upd2times2(i, j, 1);
		}
	}
}

int swap_seats(int a, int b) {
	change(x[a], y[a], -1);
	num[x[a]][y[a]] = b;
	change(x[a], y[a], 1);


	change(x[b], y[b], -1);
	num[x[b]][y[b]] = a;
	change(x[b], y[b], 1);

	swap(x[a], x[b]);
	swap(y[a], y[b]);

	push(1, 0, len - 1);
	return t[1].mn == 4 ? t[1].ct : 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 6 / 6
• Subtask 3: 20 / 20
• Subtask 4: 6 / 6
• Subtask 5: 0 / 33
• Subtask 6: 0 / 30