Submission #1240307

#	Time	Username	Problem	Language	Result	Execution time	Memory
1240307		Ghulam_Junaid	Stations (IOI20_stations)	C++17	100 / 100	306 ms	588 KiB

stations

#include <bits/stdc++.h>
#include "stations.h"
// #include "stub.cpp"
using namespace std;

const int N = 1e3 + 10;
int sz[N];
vector<int> res, g[N];

void dfs(int v, int p = -1){
    sz[v] = 1;
    for (int u : g[v]){
        if (u == p) continue;
        dfs(u, v);
        sz[v] += sz[u];
    }
}

void assign(int v, int l = 1, int p = -1, int dist = 0){
    if (dist % 2 == 0)
        res[v] = l + sz[v] - 1;
    else
        res[v] = l;

    // cout << v << " : " << res[v] << endl;

    int prv = 0;
    for (int u : g[v]){
        if (u == p) continue;
        assign(u, l + (res[v] == l) + prv, v, dist + 1);
        prv += sz[u];
    }
}

vector<int> label(int n, int k, vector<int> u, vector<int> v) {
	res.resize(n);
    for (int i = 0; i < n; i ++) g[i].clear();
    for (int i = 0; i < n - 1; i ++){
        g[u[i]].push_back(v[i]);
        g[v[i]].push_back(u[i]);
    }
    dfs(0);
    assign(0);
	return res;
}

int find_next_station(int s, int t, vector<int> c) {
    if (c.size() == 1) return c[0];
    if (s < c[0]){ // I am the one who says everyone in subtree is >= s
        if (t < s or t > c[c.size() - 2]) return c.back();
        return *lower_bound(c.begin(), c.end(), t);
    }
    else{ // <= s
        if (t > s or t < c[1]) return c[0];
        return c[upper_bound(c.begin(), c.end(), t) - c.begin() - 1];
    }
}

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