Submission #1187351

#	Time	Username	Problem	Language	Result	Execution time	Memory
1187351		swishy123	Stations (IOI20_stations)	C++20	100 / 100	307 ms	544 KiB

stations

#include <iostream>
#include <algorithm>
#include <vector>
#include <random>
#include <chrono>
#include <set>
#include <map>
#include <stack>
#include <functional>
#include <iomanip>
#include <queue>
#include <cassert>
#include <complex>
#include <cstring>
#include <memory>
#include <bitset>
#include <sstream>
#include <cmath>
#include <numeric>
#include <numbers>
#include <fstream>
#include "stations.h"

using namespace std;

#ifndef template
#ifndef define
 
#define ll long long
#define ld long double
#define pl pair<ll, ll>
#define pi pair<int, int>
#define nl cout << '\n';
#define x first
#define y second 
#define cbit(x) __builtin_popcountll(x)
#define uid(a, b) uniform_int_distribution<ll>(a, b)(rng) 
#define siz(x) (int)x.size()
 
#endif
 
#ifndef print
void print(size_t x) {cout << x << ' ';}
void print(int x) {cout << x << ' ';}
void print(long long x) {cout << x << ' ';}
void print(float x) {cout << x << ' ';}
void print(long double x) {cout << x << ' ';}
void print(char x) {cout << x << ' ';}
void print(const char* x) {cout << x << ' ';}
void print(bool x) {cout << x << ' ';}
void print(string &x) {cout << x << ' ';}
 
template<typename T, typename V>
void print(pair<T, V> &p) {print(p.x); print(p.y);}
template<typename T>
void print(vector<T> v) {for (int i = 0; i < v.size(); i++) print(v[i]);}
template<typename T>
void print(vector<vector<T>> v) {
    for (int i = 0; i < v.size(); i++){
        for (int j = 0; j < v[i].size(); j++)
            print(v[i][j]);
        nl;
    }
}
template <typename T, typename... V>
void print(T t, V&&... v) {print(t); print(v...);}
 
#endif
 
#ifndef read
void read(int &x) {cin >> x;}
void read(long long &x) {cin >> x;}
void read(unsigned &x) {cin >> x;}
void read(unsigned long long &x) {cin >> x;}
void read(float &x) {cin >> x;}
void read(long double &x) {cin >> x;}
void read(char &x) {cin >> x;}
void read(string &x) {cin >> x;}
void read(bool &x) {cin >> x;}
 
template<typename T> 
void read(vector<T> &v) {
    for (int i = 0; i < v.size(); i++)
        read(v[i]);
}
template <typename T, typename... V>
void read(T &t, V&... v) {read(t); read(v...);}
#endif
 
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
template<class T> bool maxi(T& a, const T& b) {
    return a < b ? a = b, 1 : 0;
}
template<class T> bool mini(T& a, const T& b) {
    return a > b ? a = b, 1 : 0;
}
template<class... Args>
auto vec(size_t n, Args&&... args) {
    if constexpr(sizeof...(args) == 1)
        return vector(n, args...);
    else
        return vector(n, vec(args...));
}

#endif

using namespace std;
const ll inf = 1e18;
const ll def = 1e5+1;
const ll mod = 1e9+9;

using namespace std;

vector<int> label(int n, int k, vector<int> u, vector<int> v){
    vector<vector<int>> edg(n);
    for (int i = 0; i < n - 1; i++){
        edg[u[i]].push_back(v[i]);
        edg[v[i]].push_back(u[i]);
    }
    vector<int> order(n);
    int indx = 0;

    auto dfs = [&](int u, int pre, int h, auto&& dfs) -> void{
        if (h % 2 == 0)
            order[u] = indx++;
        for (int v : edg[u]){
            if (v == pre)
                continue;
            dfs(v, u, h + 1, dfs);
        }
        if (h % 2 == 1)
            order[u] = indx++;
    };
    dfs(0, -1, 0, dfs);
    return order;
}

int find_next_station(int s, int t, vector<int> c){
	bool flag = 0;
    for (int u : c){
        if (u > s)
            flag = 1;
    }
    vector<pair<pi, int>> ranges;
    int parent = -1;

    if (flag){
        for (int i = 0; i < c.size(); i++){
            if (i == 0)
                ranges.push_back({{s, c[i]}, c[i]});
            else    
                ranges.push_back({{c[i - 1] + 1, c[i]}, c[i]});
        }
        if (s != 0){
            ranges.pop_back();
            parent = c.back();
        }
    }   
    else{
        for (int i = 1; i < c.size(); i++){
            if (i == c.size() - 1)
                ranges.push_back({{c[i], s}, c[i]});
            else    
                ranges.push_back({{c[i], c[i + 1] - 1}, c[i]});
        }
        parent = c.front();
    }
    for (int i = 0; i < ranges.size(); i++){
        int u = ranges[i].y;
        auto [l, r] = ranges[i].x;

        if (t >= l && t <= r)
            return u;
    }
    return parent;
}

int find_next(int s, int t, vector<vector<int>> &edg){
    int n = edg.size();
    auto dp = vec(n, 0);

    auto dfs = [&](int u, int pre, auto&& dfs) -> void{
        if (u == t)
            dp[u] = 1;
        for (int v : edg[u]){
            if (v == pre)
                continue;
            dfs(v, u, dfs);
            dp[u] |= dp[v];
        }
    };
    dfs(s, -1, dfs);
    for (int v : edg[s]){
        if (dp[v])
            return v;
    }
    return -1;
}

// void solve(){
//     int n, q;
//     read(n, q);

//     print("Generated edges:"); nl;
//     vector<int> u(n - 1), v(n - 1);
//     vector<vector<int>> edg(n);

//     for (int i = 0; i < n - 1; i++){
//         u[i] = i + 1;
//         v[i] = uid(0, i);
//         print(u[i], v[i]); nl;
//     }
//     vector<int> order = label(n, n, u, v);
//     print("New label:"); nl;
//     print(order); nl;

//     print("New edges:"); nl;
//     for (int i = 0; i < n - 1; i++){
//         edg[order[u[i]]].push_back(order[v[i]]);
//         edg[order[v[i]]].push_back(order[u[i]]);
//         print(order[u[i]], order[v[i]]); nl;
//     }
//     while (q--){
//         int s = uid(0, n - 1), t = s;
//         while (s == t)
//             t = uid(0, n - 1);

//         sort(edg[s].begin(), edg[s].end());
//         nl; print("Query:", "s =", s, "t =", t, "c =", edg[s]); nl;
//         int res = find_next_station(s, t, edg[s]);
//         int expected = find_next(s, t, edg);
        
//         if (res != expected){
//             print("Result:", res); nl;
//             print("Expected:", expected); nl;
//         }
//     }
// }

// int32_t main(){
//     ios_base::sync_with_stdio(0);
//     cin.tie(0); cout.tie(0);

//     if (ifstream("input.txt").good()){
//         freopen("input.txt", "r", stdin);
//         freopen("output.txt", "w", stdout);
//     }

//     int t = 1;
//     while (t--){
//         solve();
//         nl;
//     }

//     return 0;
// }

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