제출 #45493

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
45493		Abelyan	장난감 기차 (IOI17_train)	C++17	49 / 100	2041 ms	1920 KiB

train

#include "train.h"
#include <algorithm>
#include <vector>
#include <unordered_set>
#include <queue>
using namespace std;

const int N = 5006;
int n, m;
vector<int> g[N],ing[N];
bool col[N],chrg[N];


void rev(vector<bool> &s, vector<bool> &ans){
	for (int i = 0; i < n; i++){
		ans[i] = !s[i];
	}
}
void Fw(int w, const vector<bool> &s, vector<bool> &ans){
	static queue<int> q;
	ans.resize(0);
	for (int i = 0; i < s.size(); i++){
		ans.push_back(s[i]); 
		if (s[i])
			q.push(i);
	}
	while (!q.empty()){
		int v = q.front();
		q.pop();
		for (auto to : ing[v]){
			if (ans[to]) continue;
			bool mb = true;
			for (auto k : g[to]){
				mb &= ans[k] == true;
			}
			if (col[to] == w || mb){
				ans[to] = true;
				q.push(to);
			}
		}
	}
}

void intersect(const vector<bool> &a, const vector<bool> &b, vector<bool> &ans){
	ans.resize(0);
	for (int i = 0; i < a.size();i++){
		ans.push_back(b[i] && a[i]);
	}
}

vector<int> who_wins(vector<int> a, vector<int> r, vector<int> u, vector<int> v) {
	n = a.size();
	m = u.size();
	for (int i = 0; i < m; i++){
		g[u[i]].push_back(v[i]);
		ing[v[i]].push_back(u[i]);
	}
	for (int i = 0; i < n; i++){
		if (a[i]){
			col[i] = true;
		}
	}
	for (int i = 0; i < n; i++){
		if (r[i]) chrg[i] = true;
	}
	
	while (1){
		static vector<bool> R(n);
		for (int i = 0; i < n; i++){
			R[i] = chrg[i];
		}
		static vector<bool>  far(n), gg(n) , x(n), ht(n);
		Fw(1, R, far);
		rev(far, gg);
		Fw(0, gg, x);
		intersect(far, x, ht);
		bool mb = false;
		for (int i = 0; i < ht.size();i++){
			if (ht[i] && chrg[i]) mb = true, chrg[i] = false;
		}
		if (!mb){
			vector<int> ans(n,1);
			for (int i = 0; i < x.size();i++){
				if (x[i])
					ans[i] = 0;
			}
			return ans;
		}
	}
}
/*
2 4 
0 1 
1 0 
0 0 
0 1 
1 0 
1 1 

*/

컴파일 시 표준 에러 (stderr) 메시지

train.cpp: In function 'void Fw(int, const std::vector<bool>&, std::vector<bool>&)':
train.cpp:22:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < s.size(); i++){
                  ~~^~~~~~~~~~
train.cpp: In function 'void intersect(const std::vector<bool>&, const std::vector<bool>&, std::vector<bool>&)':
train.cpp:46:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < a.size();i++){
                  ~~^~~~~~~~~~
train.cpp: In function 'std::vector<int> who_wins(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
train.cpp:78:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int i = 0; i < ht.size();i++){
                   ~~^~~~~~~~~~~
train.cpp:83:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int i = 0; i < x.size();i++){
                    ~~^~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 11 / 11
• Subtask 4: 11 / 11
• Subtask 5: 12 / 12
• Subtask 6: 0 / 51