Submission #243173

#	Time	Username	Problem	Language	Result	Execution time	Memory
243173		crossing0ver	Toy Train (IOI17_train)	C++17	5 / 100	1260 ms	1788 KiB

train

#include<bits/stdc++.h>
#define vi vector<int>
#define pb push_back
//#include "train.h"
using namespace std;
int n,m;
vi X,Y,good,who,adj[5009];

vi CASE1() {
	vi ans(n);
	for (int i = n-1; i >= 0; i--) {
		bool flag = 0;
		for (int j : adj[i]) {
			if (j == i && who[i] == good[i]) {
				ans[i] = who[i];
				flag = 1;
				break;
			}
			if (who[i] == ans[j] && j != i) {
				flag = 1;
				ans[i] = ans[j];
				break;
			}
		}
		if (flag == 0) ans[i] = (!who[i]);
	}
	return ans;
}
vector<int> vis(5005),P(5005),G(5005),depth(5005);
bool dfs(int v) {
	vis[v] = 1;
	if (good[v]) G[v] = v;
		else if (P[v] != -1) G[v] = G[P[v]];
		else G[v] = -1;
		
	bool ans = 0;
	for (int i : adj[v]) {
		if (vis[i]) {
			if (G[v] != -1 && depth[G[v]] >= depth[i]) 
				ans = 1;
			}
		else {depth[i] = depth[v] + 1; P[i] = v;ans |= dfs(i);}
	}    
	return ans;
}
vi CASE2() {
	vi ans(n);//,vis(n),P(n),G(n),depth(n);
	for (int i = 0; i < n; i++) {
		for (int i = 0 ; i < n; i++) {
			P[i] = G[i] = vis[i] = depth[i] = 0;
		}
		P[i] = -1;
		ans[i] = dfs(i);
	/*	fill(P.begin(),P.end(),0);
		fill(G.begin(),G.end(),0);
		fill(vis.begin(),vis.end(),0);
		fill(depth.begin(),depth.end(),0);*/
	}
	return ans;
}
vi who_wins(vi a1, vi r, vi st, vi en) {
	n = a1.size(), m = st.size();
	X = st; Y = en;
	for (int i = 0; i < m; i++)
		adj[X[i]].pb(Y[i]);
	good = r;
	who = a1;
	bool case1 = 1,case2 = 1;
	for (int i = 0; i < m; i++) {
		if (X[i] != Y[i] && X[i]+1 != Y[i])
			case1 = 0;
	}
	for (int i = 0;i < n; i++)
		if (who[i] == 0) case2 = 0;
	if (case2) return CASE2();
	if (case1) return CASE1();
//	return res;
	return vector<int>();
}
/*
main() {
	cin >> n >> m;
	vi r(n),a1(n),st(m),en(m);
	for (int i = 0; i < n; i++) 
		cin >> a1[i];
	for (int i = 0; i < n ;i++)
		cin >> r[i];
	for (int i = 0; i < m ;i++) {
		int x,y;
		cin >> st[i] >> en[i];
	}
	vi ans = who_wins(a1,r,st,en);
	for (int i :ans) cout << i <<' ';
}*/

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