Submission #1068665

#	Time	Username	Problem	Language	Result	Execution time	Memory
1068665		Abito	Toy Train (IOI17_train)	C++17	0 / 100	706 ms	1760 KiB

train

#include "train.h"
#include <bits/stdc++.h>
//#define int long long
#define pb push_back
using namespace std;
const int N=5005;
int n,vis[N];
bool a[N],c[N],cyc[N],h,self[N],par[N],sz[N];
vector<int> adj[2][N],t;
void dfs0(int x){
	vis[x]=1;
	for (auto u:adj[0][x]){
		if (vis[u]) continue;
		dfs0(u);
	}t.pb(x);
	return;
}
int getpar(int x){
	if (par[x]==x) return x;
	return par[x]=getpar(par[x]);
}
void link(int x,int y){
	x=getpar(x);
	y=getpar(y);
	if (x==y) return;
	if (sz[x]>sz[y]) swap(x,y);
	sz[y]+=sz[x];
	par[x]=y;
	return;
}
void dfs1(int x,int p){
	vis[x]=1;
	link(x,p);
	for (auto u:adj[1][x]) if (!vis[u]) dfs1(u,p);
	return;
}
bool getans(int s){
	queue<int> q;
	q.push(s);
	vis[s]=1;
	bool ok=0;
	while (!q.empty()){
		int x=q.front();
		//cout<<x<<' ';
		q.pop();
		if (c[x]){
			if (sz[getpar(x)]>1) ok=1;
			if (self[x]==1) ok=1;
		}
		for (auto u:adj[0][x]){
			if (vis[u]) continue;
			else{
				vis[u]=1;
				q.push(u);
			}
		}
	}//cout<<endl;
	return ok;
}
std::vector<int32_t> who_wins(std::vector<int32_t> A, std::vector<int32_t> r, std::vector<int32_t> u, std::vector<int32_t> v) {
	n=A.size();
	for (int i=1;i<=n;i++) a[i]=A[i-1],c[i]=r[i-1],par[i]=i,sz[i]=1;
	for (int i=0;i<u.size();i++){
		adj[0][u[i]+1].pb(v[i]+1);
		adj[1][v[i]+1].pb(u[i]+1);
		if (u[i]==v[i]) self[u[i]+1]=1;
	}
	vector<int> ans(n);
	for (int i=1;i<=n;i++){
		if (vis[i]) continue;
		dfs0(i);
	}
	memset(vis,0,sizeof(vis));
	reverse(t.begin(),t.end());
	for (auto u:t) if (!vis[u]) dfs1(u,u);
	memset(vis,0,sizeof(vis));
	for (int i=1;i<=n;i++){
		ans[i-1]=getans(i);
		memset(vis,0,sizeof(vis));
	}
	return ans;
}

Compilation message (stderr)

train.cpp: In function 'bool getans(int)':
train.cpp:47:21: warning: comparison of constant '1' with boolean expression is always false [-Wbool-compare]
   47 |    if (sz[getpar(x)]>1) ok=1;
      |        ~~~~~~~~~~~~~^~
train.cpp: In function 'std::vector<int> who_wins(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
train.cpp:63:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   63 |  for (int i=0;i<u.size();i++){
      |               ~^~~~~~~~~

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