Submission #826643

#	Time	Username	Problem	Language	Result	Execution time	Memory
826643		HorizonWest	Stations (IOI20_stations)	C++17	100 / 100	920 ms	752 KiB

stations

#include <bits/stdc++.h>
using namespace std;

#define endl '\n'
#define db double
#define ll __int128
#define pb push_back
#define fs first
#define sd second
#define Mod long(1e9 + 7)
#define all(x) x.begin(), x.end()
#define unvisited long(-1)
#define Eps double(1e-9)
#define _for(i, n) for(int i = 0; i < (n); i++)
#define dbg(x) cout << #x ": " << x << endl;

const int Max = 1e6 + 7, Inf = 1e9 + 7;

void print(bool x) { cout << (x ? "YES" : "NO") << endl; }

string tostring (__int128 x)
{
    string ans = "";
    while(x > 0)
    {
        ans += (x % 10 + '0');
        x /= 10;
    }
    reverse(all(ans));
    return ans;
}

vector <vector<int>> fx; vector <int> fy; int idx;

void dfs(int node, int parent, int depth)
{
    if(depth % 2 == 0)
    {
        idx++;
        fy[node] = idx;
    }

    for(auto& u : fx[node]) if(u != parent)
    {
        dfs(u, node, depth + 1);
    }

    if(depth % 2 == 1)
    {
        idx++;
        fy[node] = idx;
    }
}

void show()
{
    cout << "\n Labels: \n";
    for(int i = 0; i < (int) fy.size(); i++)
        cout << fy[i] << " ";
    cout << endl;
}

vector<int> label(int n, int k, vector<int> U, vector<int> V)
{
    fx.clear(); fx.assign(n, vector <int> ());
    fy.clear(); fy.assign(n, 0); idx = 0;
    for(int i = 0; i < n - 1; i++)
    {
        fx[V[i]].push_back(U[i]);
        fx[U[i]].push_back(V[i]);
    }
    //for(int i = 0; i < n; i++)
    //{
    //    if(fy[i] == 0) dfs(i, -1);
    //}
    dfs(0, -1, 1);
    //show();
    return fy;
}

int find_next_station(int s, int t, vector<int> c)
{
    int n = (int) c.size(); sort(all(c));

    if(s > c[0])
    {
        for(int i = n - 1; i >= 0; i--)
        {
            if(c[i] <= t && t <= s)
                return c[i];
        }
        return c[0];
    }
    else
    {
        for(int i = 0; i < n; i++)
        {
            if(s <= t && t <= c[i])
                return c[i];
        }
        return c[n-1];
    }
}

/**
1
5 10
0 1
1 2
1 3
2 4
2
2 0 1
1 3 3


9
1
3
*/

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