Submission #80942

#	Time	Username	Problem	Language	Result	Execution time	Memory
80942		wzy	Robots (IOI13_robots)	C++11	100 / 100	2716 ms	36572 KiB

robots

#include "robots.h"
#include <bits/stdc++.h>
using namespace std;
#define pii pair<int,int>
#define pb push_back
#define F first
#define S second
// think about the toys as points (W[i] , S[i]) , robots as lines :
// robot A type is a vertical line in X[i]
// robot B type is a horizontal line in  Y[i]
// let R[i] be the leftmost type A robot that dominate 

vector<int> hold[2][50005];
bool used[1000005];
int putaway(int A, int B, int T, int X[], int Y[], int W[], int S[]) {
	vector<int> vert, hori;
	for(int i = 0 ; i < A ; i++){
		vert.push_back(X[i]);
	}
	for(int i = 0 ; i < B; i++){
		hori.push_back(Y[i]);
	}
	sort(vert.begin() , vert.end());
	sort(hori.begin() , hori.end());
	for(int i = 0 ; i < T ; i++){
		int l = 0 , r = vert.size();
		r--;
		int ansj = -1;
		while(l<=r){
			int mid = (l+r)/2;
			if(vert[mid] > W[i]){
				ansj = mid;
				r = mid - 1;
			}
			else l = mid + 1;
		}
		if(ansj>=0){
			hold[0][ansj].push_back(i);
		}
		l = 0 , r = hori.size();
		r--;
		ansj = -1;
		while(l<=r){
			int mid = (l+r)/2;
			if(hori[mid] > S[i]){
				ansj = mid;
				r = mid - 1;
			}
			else l = mid + 1;
		}
		if(ansj>=0){
			hold[1][ansj].push_back(i);
		}
	}
	int l = 1 , r = (int) 1e6;
	int ansj = -1;
	while(l<=r){
		int mid = (l+r)/2;
		bool can = true;
		for(int i = 0 ; i <= T ;i ++){
			used[i] = false;
		}
		int lol = 0;
		// solve now
		// pega os caras pra X
		priority_queue<pii> pq;
		for(int i = 0 ; i < A ; i++){
			for(int j = 0 ; j < hold[0][i].size() ; j++) pq.push(pii(S[hold[0][i][j]] , hold[0][i][j]));
			int cnt = mid;
			while(cnt-- && pq.size()){
				pii u = pq.top();
				pq.pop();
				used[u.S] = true;
				lol++;
			}
		}
		while(!pq.empty()) pq.pop();
		for(int i = 0 ; i < B ; i++){
			for(int j = 0 ; j < hold[1][i].size() ; j++){
				if(used[hold[1][i][j]]) continue;
				pq.push(pii(W[hold[1][i][j]] , hold[1][i][j]));
			}
			int cnt = mid;
			while(cnt-- && pq.size()){
				pii u = pq.top();
				pq.pop();
				used[u.S] = true;
				lol++;
			}
		}
		if(lol != T) can = false;
		if(can){
			ansj = mid;
			r = mid - 1;
		}
		else l = mid + 1;
	}    
	return ansj;
}

Compilation message (stderr)

robots.cpp: In function 'int putaway(int, int, int, int*, int*, int*, int*)':
robots.cpp:68:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int j = 0 ; j < hold[0][i].size() ; j++) pq.push(pii(S[hold[0][i][j]] , hold[0][i][j]));
                    ~~^~~~~~~~~~~~~~~~~~~
robots.cpp:79:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int j = 0 ; j < hold[1][i].size() ; j++){
                    ~~^~~~~~~~~~~~~~~~~~~

• Subtask 1: 14 / 14
• Subtask 2: 14 / 14
• Subtask 3: 25 / 25
• Subtask 4: 37 / 37
• Subtask 5: 10 / 10