Submission #794327

#	Time	Username	Problem	Language	Result	Execution time	Memory
794327		Sohsoh84	Seats (IOI18_seats)	C++17	100 / 100	2530 ms	110696 KiB

seats

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

using namespace std;

typedef pair<int, int> pll;

#define X		first
#define Y		second
#define all(x)		(x).begin(), (x).end()
#define sep		' '
#define debug(x)	cerr << #x << ": " << x << endl;

const int MAXN = 1e6 + 10;

int n, m, R[MAXN], C[MAXN], k;

namespace segment {
	pll sg[MAXN << 2];
	int lz[MAXN << 2];
	
	inline pll merge(pll a, pll b) {
		if (a.X == b.X) return {a.X, a.Y + b.Y};
		return min(a, b);
	}

	void build(int l = 0, int r = k - 1, int v = 1) {
		if (l == r) sg[v] = {0, 1};
		else {
			int mid = (l + r) >> 1;
			build(l, mid, v << 1);
			build(mid + 1, r, v << 1 | 1);
			sg[v] = merge(sg[v << 1], sg[v << 1 | 1]);
		}
	}

	inline void push(int v) {
		sg[v].X += lz[v];
		if ((v << 1 | 1) < (MAXN << 2)) {
			lz[v << 1] += lz[v];
			lz[v << 1 | 1] += lz[v];
		}

		lz[v] = 0;
	}

	void update(int ql, int qr, int val, int l, int r, int v) {
		push(v);
		if (ql > r || qr < l) return;
		if (ql <= l && qr >= r) {
			lz[v] += val;
			push(v);
			return;
		}

		int mid = (l + r) >> 1;
		update(ql, qr, val, l, mid, v << 1);
		update(ql, qr, val, mid + 1, r, v << 1 | 1);
		sg[v] = merge(sg[v << 1], sg[v << 1 | 1]);
	}

	void update(int l, int r, int val) {	
		if (r < l) return;
		r = min(r, k-1);
		update(l, r, val, 0, k-1, 1);
		
//		cerr << l << sep << r << endl;
	}
}

vector<vector<int>> A;

inline void add(int i, int j, int z) {
	vector<int> vec;
	for (int a = 0; a < 2; a++)
		for (int b = 0; b < 2; b++)
			vec.push_back({A[i + a][j + b]});

	sort(all(vec));
	segment::update(vec[0], vec[1] - 1, z);
	segment::update(vec[2], vec[3] - 1, z);
}

void give_initial_chart(int H_, int W_, vector<int> R_, vector<int> C_) {
	n = H_, m = W_;
	k = n * m;
	
	segment::build();

	A.resize(n + 5);
	for (int i = 0; i < n + 5; i++) {
		A[i].resize(m + 5, MAXN);
	}
	
	for (int i = 0; i < k; i++) {
		R[i] = R_[i] + 1;
		C[i] = C_[i] + 1;
		A[R[i]][C[i]] = i;
	}

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

int swap_seats(int a, int b) {	
	for (int i = 0; i < 2; i++)
		for (int j = 0; j < 2; j++)
			add(R[a] - i, C[a] - j, -1);

	A[R[a]][C[a]] = b;	

	for (int i = 0; i < 2; i++)
		for (int j = 0; j < 2; j++)
			add(R[a] - i, C[a] - j, 1);


	for (int i = 0; i < 2; i++)
		for (int j = 0; j < 2; j++)
			add(R[b] - i, C[b] - j, -1);

	A[R[b]][C[b]] = a;
	for (int i = 0; i < 2; i++)
		for (int j = 0; j < 2; j++)
			add(R[b] - i, C[b] - j, 1);



	swap(R[a], R[b]);
	swap(C[a], C[b]);
	auto [_, cnt] = segment::sg[1];
	return cnt;
}

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