Submission #1046708

#	Time	Username	Problem	Language	Result	Execution time	Memory
1046708		MarwenElarbi	Stations (IOI20_stations)	C++17	0 / 100	1 ms	1112 KiB

stations

#include <bits/stdc++.h>
using namespace std;
#include "stations.h"
#define pb push_back
const int nax=10005;
vector<int> adj[nax];
int tin[nax];
int tout[nax];
vector<int> ans(nax);
int timer=-1;
void compute(int x,int p){
    tin[x]=++timer;
    for(auto u:adj[x]){
        if(u==p) continue;
        compute(u,x);
    }
    tout[x]=timer;
    return;
}
void dfs1(int x,int p,int dep,int cnt){
    if(dep==0){
        ans[x]=tin[x]-cnt;
        assert(ans[x]<0);
    }else cnt++;
    for(auto u:adj[x]){
        if(u==p) continue;
        dfs1(u,x,dep^1,cnt);
    }
    return;
}
void dfs2(int x,int p,int dep,int cnt){
    if(dep==1){
        ans[x]=tout[x]-cnt;
        cnt++;
        assert(ans[x]<0);
    }
    vector<int> cur;
    for(auto u:adj[x]){
        cur.pb(u);
    }
    reverse(cur.begin(),cur.end());
    for(auto u:cur){
        if(u==p) continue;
        dfs2(u,x,dep^1,cnt);
    }
    return;
}
std::vector<int> label(int n, int k, std::vector<int> u, std::vector<int> v) {
    ans.resize(n);
    for (int i = 0; i < n-1; i++) {
        int x=u[i];
        int y=v[i];
        adj[x].pb(y);
        adj[y].pb(x);
    }
    compute(0,-1);
    dfs1(0,-1,0,0);
    dfs2(0,-1,0,0);
    return ans;
}

int find_next_station(int s, int t, std::vector<int> c) {
    sort(c.begin(),c.end());
    int lst;
    if(s>c.back()){
        lst=c.back();
        if(t>s) return c[0];
        for (int i = c.size()-1; i >= 0; --i)
        {
            lst=c[i];
            if(c[i]<=t) break;
        }
    }else{
        lst=c[0];
        if(t<s) return c.back();
        for (int i = 0; i < c.size(); ++i)
        {
            lst=c[i];
            if(c[i]>=t) break;
        }
    }
    return lst;
}

Compilation message (stderr)

stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:76:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   76 |         for (int i = 0; i < c.size(); ++i)
      |                         ~~^~~~~~~~~~

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