Submission #1132387

#	Time	Username	Problem	Language	Result	Execution time	Memory
1132387		StefanSebez	Stations (IOI20_stations)	C++20	36.13 / 100	310 ms	2900 KiB

stations

#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pb push_back
#define ll long long
#define ld long double
const int N=1e5+50,M=1050;
vector<int>E[N];
int in[N],out[N],nc=-1;
void DFS(int u,int parent=-1){
    in[u]=++nc;
    for(auto i:E[u]){
        if(i!=parent) DFS(i,u);
    }
    out[u]=nc;
}
std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v){
    for(int i=0;i<n-1;i++){
        E[u[i]].pb(v[i]);
        E[v[i]].pb(u[i]);
    }
    int root=0;
    /*for(int i=0;i<n;i++){
        if(E[i].size()==1) root=i;
    }*/
    DFS(root);
    vector<int>lbl;for(int i=0;i<n;i++) lbl.pb(in[i]+M*out[i]);
    for(int i=0;i<=n;i++) E[i].clear(),in[i]=out[i]=0,nc=-1;
    return lbl;
}
int IN(int x){return x%M;}
int OUT(int x){return x/M;}
bool Podstablo(int x,int y){if(IN(x)<=IN(y)&&IN(y)<=OUT(x))return true;return false;}
int find_next_station(int s, int t, std::vector<int> c){
    /*int res=c[0];
    if(s<t){
        for(int i=0;i<c.size();i++){
            int u=c[i];
            if(u>s) res=u;
        }
    }
    else{
        for(int i=0;i<c.size();i++){
            int u=c[i];
            if(u<s) res=u;
        }
    }*/
    int res=c[0];
    //if(IN(s)<=IN(t)&&IN(t)<=OUT(s)){
    if(Podstablo(s,t)){
        for(auto i:c){
            //if(IN(i)<=IN(t)&&IN(t)<=OUT(i)) res=i;
            if(Podstablo(i,t)&&!Podstablo(i,s)) res=i;
        }
    }
    else{
        for(auto i:c){
            //if(IN(i)<=IN(s)&&IN(s)<=OUT(i)) res=i;
            if(Podstablo(i,s)) res=i;
        }
    }
    return res;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 8
• Subtask 3: 0 / 16
• Subtask 4: 10 / 10
• Subtask 5: 26.1348 / 61