Submission #424118

#	Time	Username	Problem	Language	Result	Execution time	Memory
424118		cfalas	Toy Train (IOI17_train)	C++14	0 / 100	121 ms	50856 KiB

train

#include "train.h"
#include<bits/stdc++.h>
using namespace std;
#define mp make_pair
#define INF 10000000
#define MOD 1000000007
#define MID ((l+r)/2)
#define HASHMOD 2305843009213693951
#define ll long long
#define ull unsigned long long
#define F first
#define S second
typedef pair<ll, ll> ii;
typedef pair<ii, int> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef map<int, int> mii;

#define EPS 1e-6
#define FOR(i,n) for(int i=0;i<((int)(n));i++)
#define FORi(i,a,b) for(int i=((int)(a));i<((int)(b));i++)
#define FOA(v, a) for(auto &v : a)
#define len(x) ((int)x.size())

int c=0;
vector<vi> adj;
vector<vi> rev;
vi vis;

vector<int> path;
vii loops;
vector<vi> paths;
void dfs(int s){
	path.push_back(s);
	vis[s] = c;
	paths[s] = path;
	for(auto v : adj[s]){
		if(!vis[v]) dfs(v);
		else if(vis[v]==c){
			loops.push_back({s,v});
		}
	}
	path.erase(path.end()-1);
}

vi who_wins(vi a, vi r, vi u, vi v) {
	int n = len(a);
	adj.resize(n);
	rev.resize(n);
	paths.resize(n);
	vis.assign(n,0);
	vi res(n, 0);

	FOR(i, len(u)){
		adj[u[i]].push_back(v[i]);
		rev[v[i]].push_back(u[i]);
	}
	FOR(i,n){
		if(!vis[i]){
			c++, dfs(i);
		}
	}

	FOA(loop, loops){
		bool start = true;
		bool win = true;
		vi path;
		FOA(v,paths[loop.F]){
			if(v==loop.S) start = true;
			if(start){
				if(r[v]) win = true;
				path.push_back(v);
			}
		}
		if(win && !res[loop.F]){
			queue<int> q;
			FOA(v,path) q.push(v);
			vi used(n, 0);
			while(!q.empty()){
				int t = q.front();
				q.pop();
				res[t] = 1;
				FOA(v,rev[t]){
					if(!used[v]){
						used[v] = true;
						q.push(v);
					}
				}
			}
		}
	}

	return res;
}

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