Submission #704026

#	Time	Username	Problem	Language	Result	Execution time	Memory
704026		Abrar_Al_Samit	Toy Train (IOI17_train)	C++17	100 / 100	389 ms	1672 KiB

train

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

const int nax = 5000;
int n, m;
vector<int>g[nax], gt[nax];
vector<int>A, R;

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]);
		gt[v[i]].push_back(u[i]);
	}

	A = a, R = r;
	vector<int>res(n);
	int need[n];
	bool trap[n], nontrap[n];

	while(1) {
		queue<int>q;
		for(int i=0; i<n; ++i) {
			need[i] = trap[i] = nontrap[i] = 0;
		}
		for(int i=0; i<n; ++i) {
			if(R[i]) nontrap[i] = 1, q.push(i);
			else trap[i] = 1;
		}

		for(int i=0; i<n; ++i) {
			if(nontrap[i]) continue;
			if(A[i]) need[i] = 1;
			else need[i] = g[i].size();
		}


		while(!q.empty()) {
			int v = q.front(); q.pop();
			trap[v] = 0, nontrap[v] = 1;
			for(int to : gt[v]) {
				if(--need[to]==0) {
					q.push(to);
				}
			}
		}

		vector<int>trans;
		bool did = false;
		for(int x=0; x<n; ++x) if(nontrap[x]) {
			bool all = true, one = false;
			for(int to : g[x]) {
				all &= trap[to];
				one |= trap[to];
			}

			if(A[x] && all) {
				nontrap[x] = 0, trap[x] = 1, R[x] = 0;
				did = 1;
			} else if(!A[x] && one) {
				nontrap[x] = 0, trap[x] = 1, R[x] = 0;
				did = 1;
			}
		}
		if(!did) {
			for(int x=0; x<n; ++x) if(nontrap[x]) {
				res[x] = 1;
			}
			break;
		}
	}
	return res;
}

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