Submission #616187

#	Time	Username	Problem	Language	Result	Execution time	Memory
616187		John3_141592	Stations (IOI20_stations)	C++14	5 / 100	967 ms	672 KiB

stations

#include "stations.h"
#include <bits/stdc++.h>

using namespace std;

vector <int> grafo[1003];
map <int,bool> mapa;
int arr[1003];
bool vis[1003];

void dfs1(int node,int c){
    vis[node]=true,arr[node]=c;
    for(auto i:grafo[node]) if(!vis[i]) dfs1(i,c+1);
}

void dfs2(int node,int c){
    vis[node]=true,arr[node]=c;
    for(auto i:grafo[node]) if(!vis[i]) dfs2(i,c-1);
}

std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v) {
    if(n==2){
        vector <int> vec;
        vec.push_back(0);
        vec.push_back(1);
        return vec;
    }
    mapa.clear();
    for(int i=0;i<n;i++) grafo[i].clear();
    for(int i=0;i<n-1;i++){
        grafo[u[i]].push_back(v[i]);
        grafo[v[i]].push_back(u[i]);
    }
    int a=-1,b=-1,c=-1;
    for(int i=0;i<n;i++){
        if(grafo[i].size()==1){
            if(a==-1) a=i;
            else b=i;
        }
        if(grafo[i].size()>2) c=i;
    }
    if(c==-1) c=grafo[a][0];
    else{
        for(auto i:grafo[c]) mapa[i]=true;
        a=-1,b=-1;
        for(int i=0;i<n;i++){
            if(grafo[i].size()==1 && !mapa.count(i)){
                if(a==-1) a=i;
                else b=i;
            }
        }
        if(a==-1){
            for(auto i:grafo[c]){
                if(grafo[i].size()!=1) continue;
                if(a==-1) a=i;
                else b=i;
            }
        }
        else if(b==-1){
            for(auto i:grafo[c]){
                if(grafo[i].size()!=1) continue;
                if(b==-1) b=i;
            }
        }
    }
    fill(arr,arr+n+1,0);
    fill(vis,vis+n+1,false);
    vis[c]=true;
    int aux=0;
    dfs1(a,0);
    for(int i=0;i<n;i++) if(vis[i] && i!=c) aux++;
    dfs2(b,n-1);
    arr[c]=aux++;
    for(int i=0;i<n;i++) if(!vis[i]) arr[i]=aux++;
    vector <int> solve;
    for(int i=0;i<n;i++) solve.push_back(arr[i]);
    return solve;
}

int find_next_station(int s, int t, std::vector<int> c) {
    if(c.size()==1) return c[0];
    if(c.size()==2){
        if(s<t) return c[1];
        return c[0];
    }
    bool band=false;
    for(auto i:c) if(t==i) band=true;
    if(band) return t;
    if(s<t) return c.back();
    return c[0];
}

• Subtask 1: 5 / 5
• Subtask 2: 0 / 8
• Subtask 3: 0 / 16
• Subtask 4: 0 / 10
• Subtask 5: 0 / 61