Submission #311980

#	Time	Username	Problem	Language	Result	Execution time	Memory
311980		MonkeyKing	Stations (IOI20_stations)	C++14	100 / 100	916 ms	1280 KiB

stations

#include <bits/stdc++.h>
#include "stations.h"
#define all(x) x.begin(),x.end()
using namespace std;
vector <int> edges[1005];
int dfn;

void dfs(int x,int depth,int par,vector <int> &res)
{
    if(depth & 1)
    {
        res[x]=dfn++;
        for(auto u:edges[x])
        {
            if(u==par) continue;
            dfs(u,depth+1,x,res);
        }
    }
    else
    {
        for(auto u:edges[x])
        {
            if(u==par) continue;
            dfs(u,depth+1,x,res);
        }
        res[x]=dfn++;
    }
}

vector <int> label(int n,int k,vector <int> _ea,vector <int> _eb)
{
	dfn=0;
	assert((int)_ea.size()==n-1);
    vector <int> res;
    res.resize(n);
    for(int i=0;i<n;i++)
    {
    	edges[i].clear();
	}
    for(int i=0;i<n-1;i++)
    {
        edges[_ea[i]].push_back(_eb[i]);
        edges[_eb[i]].push_back(_ea[i]);
    }
    dfs(0,0,-1,res);
    return res;
}

int find_next_station(int s,int t,vector <int> c)
{
//	return 0;
    if(s>c[0]) // ºó¸ù
    {
        sort(all(c));
        int par=*c.begin();
        c.erase(c.begin());
        if(c.empty()) return par;
        if(t<c.front() || t>=s) return par;
        reverse(all(c));
        for(auto x:c)
        {
            if(t>=x) return x;
        }
    }
    else // Ïȸù
    {
        sort(all(c));
        int par=*(--c.end());
        c.erase(--c.end());
        if(c.empty()) return par;
        if(t>c.back() || t<=s) return par;
        for(auto x:c)
        {
            if(t<=x) return x;
        }
    }
    // assert(false);
    return -1;
}

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