Submission #294388

#	Time	Username	Problem	Language	Result	Execution time	Memory
294388		eohomegrownapps	Toy Train (IOI17_train)	C++14	0 / 100	11 ms	1536 KiB

train

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

int n,m;

vector<vector<int>> adjlist;
vector<vector<int>> revadjlist;

vector<int> aowns;
vector<int> charging;

vector<int> used; // 0 - eliminated, 1 - unvisited, 2 - in f
vector<int> awins;

void genSet(bool player){
	vector<int> numconnected(n,0);
	queue<int> q;
	for (int i = 0; i<n; i++){
		if (used[i]==2){
			q.push(i);
		}
		if (used[i]==0){
			for (int x : revadjlist[i]){
				numconnected[x]++;
			}
		}
	}
	while (q.size()>0){
		int f = q.front();
		q.pop();
		for (int i : revadjlist[f]){
			if (used[i]!=1){continue;}
			numconnected[i]++;
			bool stat = (player)?aowns[i]:(!aowns[i]);
			if (stat||((!stat)&&numconnected[i]==adjlist[i].size())){
				// i is in s
				used[i]=2;
				q.push(i);
			}
		}
	}
	/*for (int i : used){
		cout<<i<<' ';
	}cout<<'\n';*/
}

bool eliminate(){
	for (int i = 0; i<n; i++){
		if (used[i]!=0){
			used[i]=1;
		}
		if (charging[i]){
			used[i]=2;
		}
	}
	genSet(true);
	bool ahasall = true;
	for (int i = 0; i<n; i++){
		if (used[i]==1){
			used[i]=2;
			ahasall=false;
		} else if (used[i]==2){
			used[i]=1;
		}
	}
	/*for (int i : used){
		cout<<i<<' ';
	}cout<<'\n';*/
	if (ahasall){
		for (int i = 0; i<n; i++){
			if (used[i]==1){
				awins[i]=1;
			}
		}
		return true;
	}
	genSet(false);
	for (int i = 0; i<n; i++){
		if (used[i]==2){
			awins[i]=0;
			used[i]=0;
		}
	}
	return false;
}

std::vector<int> who_wins(std::vector<int> _aowns, std::vector<int> _charging, std::vector<int> u, std::vector<int> v) {
	aowns=_aowns;
	charging=_charging;
	n=aowns.size();
	m=u.size();
	//cout<<"blah"<<endl;
	//cout<<n<<endl;
	adjlist.resize(n);
	revadjlist.resize(n);
	for (int i = 0; i<m; i++){
		//cout<<u[i]<<' '<<v[i]<<endl;
		adjlist[u[i]].push_back(v[i]);
		revadjlist[v[i]].push_back(u[i]);
	}
	//cout<<"bleh"<<endl;
	awins.resize(n);
	used.resize(n,1);

	while (!eliminate()){
		continue;
	}

	return awins;
}

Compilation message (stderr)

train.cpp: In function 'void genSet(bool)':
train.cpp:36:39: warning: comparison of integer expressions of different signedness: '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'} and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   36 |    if (stat||((!stat)&&numconnected[i]==adjlist[i].size())){

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