Submission #794426

#	Time	Username	Problem	Language	Result	Execution time	Memory
794426		firewater	Toy Train (IOI17_train)	C++14	11 / 100	8 ms	2132 KiB

train

#include "train.h"
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
#include <cassert>
#define ll long long
#define MX 20230
using namespace std;
int n,m,tot,w,p[MX],a[MX],c[MX],cc[MX],h[MX],H[MX],fr[MX],cy[MX];
vector<int>ls,s[MX];
struct rec
{
	int to,nx;
}e[MX],E[MX];
void addl(int x,int y)
{
	e[++tot].to=y;
	e[tot].nx=h[x];
	h[x]=tot;
	return;
}
void addll(int x,int y)
{
	E[tot].to=y;
	E[tot].nx=H[x];
	H[x]=tot;
	return;
}
void dfs1(int x)
{
	p[x]=1;
	for(int i=h[x];i;i=e[i].nx){
		int y=e[i].to;
		if(p[y])continue;
		dfs1(y);
	}
	ls.push_back(x);
	return;
}
void dfs2(int x,int p)
{
	fr[x]=p;
	s[p].push_back(x);
	for(int i=H[x];i;i=E[i].nx){
		int y=E[i].to;
		if(fr[y])continue;
		dfs2(y,p);
	}
	return;
}
void dfs3(int x)
{
	cc[x]=1;
	for(int j=0;j<s[x].size();++j){
		int xx=s[x][j];
		for(int i=H[xx];i;i=E[i].nx){
			int y=E[i].to;
			if(cc[fr[y]])continue;
			dfs3(fr[y]);
		}
	}
	return;
}
std::vector<int> who_wins(std::vector<int> A, std::vector<int> C, std::vector<int> U, std::vector<int> V) {
	std::vector<int> ans(A.size());
	n=A.size();
	m=U.size();
	for(int i=1;i<=n;++i){
		a[i]=A[i-1];
		c[i]=C[i-1];
	}
	for(int i=0;i<m;++i){
		if(U[i]==V[i])cy[U[i]+1]=1;
		else{
			addl(U[i]+1,V[i]+1);
			addll(V[i]+1,U[i]+1);
		}
	}
	for(int i=1;i<=n;++i)
		p[i]=0;
	for(int i=1;i<=n;++i)
		if(!p[i])
			dfs1(i);
	reverse(ls.begin(),ls.end());
	for(int i=0;i<ls.size();++i)
		if(!fr[ls[i]])
			dfs2(ls[i],++w);
	for(int i=1;i<=n;++i)
		if(c[i]&&(s[fr[i]].size()>1||cy[i]==1))
			cc[fr[i]]=1;
	for(int i=1;i<=w;++i)
		if(cc[i])
			dfs3(i);
	for(int i=1;i<=n;++i)
		ans[i-1]=cc[fr[i]];
	return ans;
}

Compilation message (stderr)

train.cpp: In function 'void dfs3(int)':
train.cpp:55:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   55 |  for(int j=0;j<s[x].size();++j){
      |              ~^~~~~~~~~~~~
train.cpp: In function 'std::vector<int> who_wins(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
train.cpp:86:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   86 |  for(int i=0;i<ls.size();++i)
      |              ~^~~~~~~~~~

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