Submission #418794

#	Time	Username	Problem	Language	Result	Execution time	Memory
418794		peuch	Seats (IOI18_seats)	C++17	11 / 100	4099 ms	110284 KiB

seats

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


vector<int> r, c;
int h, w;

vector<vector<int> > seg[2];

void update(int pos, int ini, int fim, int id, int val, int x, int k);
int query(int pos, int ini, int fim, int p, int q, int x, int k);

void give_initial_chart(int H, int W, std::vector<int> R, std::vector<int> C) {
	r = R, c = C;
	h = H, w = W;
	seg[0] = vector<vector<int> > (h, vector<int> (4 * w));
	seg[1] = vector<vector<int> > (w, vector<int> (4 * h));
	for(int i = 0; i < r.size(); i++){
		update(1, 0, w, c[i], i, r[i], 0);
		update(1, 0, h, r[i], i, c[i], 1);
	}
}

int swap_seats(int a, int b) {
	swap(r[a], r[b]);
	swap(c[a], c[b]);
	update(1, 0, w, c[a], a, r[a], 0);
	update(1, 0, h, r[a], a, c[a], 1);
	update(1, 0, w, c[b], b, r[b], 0);
	update(1, 0, h, r[b], b, c[b], 1);
	int cur = 0;
	int maxi = 0;
	int maxr = r[0], minr = r[0], maxc = c[0], minc = c[0];
	int ret = 0;
	while(cur < h * w){
//		printf("\t%d (%d %d)\n", cur, r[cur], c[cur]);
		while(maxr < r[cur]){
			maxr++;
			maxi = max(maxi, query(1, 0, w, minc, maxc, maxr, 0));
		}
		while(minr > r[cur]){
			minr--;
			maxi = max(maxi, query(1, 0, w, minc, maxc, minr, 0));
		}
		while(maxc < c[cur]){
			maxc++;
			maxi = max(maxi, query(1, 0, h, minr, maxr, maxc, 1));
		}
		while(minc > c[cur]){
			minc--;
			maxi = max(maxi, query(1, 0, h, minr, maxr, minc, 1));
		}
		if(maxi == (maxr - minr + 1) * (maxc - minc + 1) - 1) ret++, cur = maxi;
		cur++;
	}
	return ret;
}

void update(int pos, int ini, int fim, int id, int val, int x, int k){
	if(ini > id || fim < id) return;
	if(ini == fim){
		seg[k][x][pos] = val;
		return;
	}
	int mid = (ini + fim) >> 1, e = pos << 1, d = e | 1;
	update(e, ini, mid, id, val, x, k);
	update(d, mid + 1, fim, id, val, x, k);
	seg[k][x][pos] = max(seg[k][x][e], seg[k][x][d]);
}

int query(int pos, int ini, int fim, int p, int q, int x, int k){
	if(ini > q || fim < p) return 0;
	if(ini >= p && fim <= q) return seg[k][x][pos];
	int mid = (ini + fim) >> 1, e = pos << 1, d = e | 1;
	return max(query(e, ini, mid, p, q, x, k), query(d, mid + 1, fim, p, q, x, k));
}

Compilation message (stderr)

seats.cpp: In function 'void give_initial_chart(int, int, std::vector<int>, std::vector<int>)':
seats.cpp:19:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   19 |  for(int i = 0; i < r.size(); i++){
      |                 ~~^~~~~~~~~~

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