Submission #401173

#	Time	Username	Problem	Language	Result	Execution time	Memory
401173		dxz05	Stations (IOI20_stations)	C++14	5 / 100	1025 ms	764 KiB

stations

#include "stations.h"
#include <bits/stdc++.h>

using namespace std;

const int MAXN = 1011;

vector<int> g[MAXN];

int tin[MAXN], last[MAXN], timer = 0;
void dfs(int v, int p){
    tin[v] = last[v] = timer++;
    for (int u : g[v]){
        if (u != p){
            dfs(u, v);
            last[v] = last[u];
        }
    }
}

bool line = true, binary = true;

vector<int> label(int n, int k, vector<int> U, vector<int> V) {
    for (int i = 0; i < n; i++) g[i].clear();
    timer = 0;

    for (int i = 0; i < n - 1; i++){
        if (U[i] > V[i]) swap(U[i], V[i]);
        g[U[i]].push_back(V[i]);
        g[V[i]].push_back(U[i]);
        if (U[i] != i / 2 || V[i] != i + 1) binary = false;
    }

    int idx = -1;
    for (int i = 0; i < n; i++){
        if (g[i].size() > 2){
            line = false;
        }
        if (g[i].size() == 1) idx = i;
    }

    dfs(idx, -1);

	vector<int> labels(n, 0);
	for (int i = 0; i < n; i++){
        if (line){
            labels[i] = tin[i];
            continue;
        }

        if (binary){
            labels[i] = i;
            continue;
        }

        labels[i] = tin[i] * 1000 + last[i];
	}

	return labels;
}

int find_next_station(int s, int t, vector<int> c) {
    if (line){
        return (s < t ? s + 1 : s - 1);
    }
    if (binary){
        while (t > 0){
            int x = (t - 1) / 2;
            if (x == s) return t;
            t = x;
        }
        return (s - 1) / 2;
    }
    int ans = c[0];
    t /= 1000;
    for (int v : c){
        int x = v / 1000, y = v % 1000;
        if (x <= t && t <= y) ans = v;
    }
    return ans;
}

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