Submission #421705

#	Time	Username	Problem	Language	Result	Execution time	Memory
421705		alireza_kaviani	Seats (IOI18_seats)	C++11	25 / 100	4067 ms	110476 KiB

seats

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

#define all(x)		(x).begin() , (x).end()

const int MAXN = 1e6 + 10;

int n , h , w , A[2][MAXN] , first[2][MAXN] , mn[2] , mx[2];
vector<int> vec[2][MAXN];

void give_initial_chart(int H, int W, vector<int> R, vector<int> C) {
	h = H; w = W; n = h * w;
	for(int i = 0 ; i < n ; i++){
		A[0][i] = R[i];
		A[1][i] = C[i];
		vec[0][A[0][i]].push_back(i);
		vec[1][A[1][i]].push_back(i);
	}
	for(int i = 0 ; i < h ; i++)	first[0][i] = *min_element(all(vec[0][i]));
	for(int i = 0 ; i < w ; i++)	first[1][i] = *min_element(all(vec[1][i]));
}

void change(int i , int x , int a , int b){
	for(int j = 0 ; j < vec[i][x].size() ; j++){
		if(vec[i][x][j] == a)	vec[i][x][j] = b;
	}
	first[i][x] = *min_element(all(vec[i][x]));
}

int swap_seats(int a, int b) {
	if(a > b)	swap(a , b);
	int ans = 0;
	for(int i = 0 ; i < 2 ; i++){
		if(A[i][a] == A[i][b])	continue;
		change(i , A[i][a] , a , b);
		change(i , A[i][b] , b , a);
		swap(A[i][a] , A[i][b]);
	}
	vector<int> vec;
	for(int i = 0 ; i < h ; i++)	vec.push_back(first[0][i]);
	for(int i = 0 ; i < w ; i++)	vec.push_back(first[1][i]);
	sort(all(vec));
	vec.resize(unique(all(vec)) - vec.begin());
	vec.push_back(n);
	mn[0] = mn[1] = MAXN;
	mx[0] = mx[1] = -1;
	for(int i = 0 ; i + 1 < vec.size() ; i++){
		int pos = vec[i];
		mn[0] = min(mn[0] , A[0][pos]); mx[0] = max(mx[0] , A[0][pos]);
		mn[1] = min(mn[1] , A[1][pos]); mx[1] = max(mx[1] , A[1][pos]);
		int x = (mx[0] - mn[0] + 1) , y = (mx[1] - mn[1] + 1);
		if(vec[i] < x * y && x * y <= vec[i + 1])	ans++;
	}
	return ans;
}

Compilation message (stderr)

seats.cpp: In function 'void change(int, int, int, int)':
seats.cpp:25:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |  for(int j = 0 ; j < vec[i][x].size() ; j++){
      |                  ~~^~~~~~~~~~~~~~~~~~
seats.cpp: In function 'int swap_seats(int, int)':
seats.cpp:48:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |  for(int i = 0 ; i + 1 < vec.size() ; i++){
      |                  ~~~~~~^~~~~~~~~~~~

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