Submission #1224691

#	Time	Username	Problem	Language	Result	Execution time	Memory
1224691		Malix	Toy Train (IOI17_train)	C++20	100 / 100	135 ms	1316 KiB

train

#include "train.h"
#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vii;
typedef pair<int,int> pi;
typedef vector<pi> pii;
typedef tuple<int,int,int> ti;
typedef vector<ll> li;
typedef vector<li> lii;
 
#define REP(i,a,b) for(int i=a;i<b;i++)
#define F first
#define S second
#define PB push_back
#define LSOne(s) ((s)&(-s))
#define all(x) (x).begin(),(x).end()
 
ll INF=1000000000000000010;
int inf=1e9+10;
ll M=1e9+7;

std::vector<int> who_wins(std::vector<int> B, std::vector<int> R, std::vector<int> U, std::vector<int> V) {
	int n=B.size();
	vii a(n);
	vi ans(n,-1),b(n,0);
	REP(i,0,U.size()){
		if(U[i]==V[i]&&R[U[i]]==B[U[i]])ans[U[i]]=R[U[i]];
		if(U[i]!=V[i]){
			a[V[i]].PB(U[i]);
			b[U[i]]++;
		}
	}
	int cnt=n;
	while(cnt){
		queue<int> q;
		vi arr,brr,vis(n,0),c=b;
		REP(i,0,n)if(R[i]&&ans[i]!=0){
			q.push(i);
			vis[i]=1;
		}
		while(!q.empty()){
			int x=q.front();
			q.pop();
			arr.PB(x);
			for(auto u:a[x])if(!vis[u]&&ans[u]==-1){
				if(B[u]==1){
					vis[u]=1;
					q.push(u);
				}
				else{
					c[u]--;
					if(c[u]==0){
						vis[u]=1;
						q.push(u);
					}
				}
			}
		}
		if(arr.size()==cnt){
			cnt=0;
			for(auto u:arr)ans[u]=1;
			continue;
		}
		vi tmp(n,1);
		for(auto u:arr)tmp[u]=0;
		vis.clear();vis.resize(n,0);
		c=b;
		REP(i,0,n)if(tmp[i]){
			q.push(i);
			vis[i]=1;
		}
		while(!q.empty()){
			int x=q.front();
			q.pop();
			brr.PB(x);
			for(auto u:a[x])if(!vis[u]&&ans[u]!=1){
				if(B[u]==0){
					vis[u]=1;
					q.push(u);
				}
				else{
					c[u]--;
					if(c[u]==0){
						vis[u]=1;
						q.push(u);
					}
				}
			}
		}
		for(auto u:brr)ans[u]=0;
		cnt=0;
		REP(i,0,n)if(ans[i]!=0)cnt++;
	}
	return ans;
}

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