제출 #425440

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
425440		tht2005	경주 (Race) (IOI11_race)	C++14	0 / 100	6 ms	8908 KiB

race

/*
 *  Written by
 *       ______  _   _  ______  ____  ____  ____  ____
 *      |_    _|| |_| ||_    _||_   || __ || __ |/  _/
 *        |  |  |  _  |  |  |    / / ||  ||||  ||| |__
 *        |  |  | | | |  |  |   | |_ ||__||||__||\__  \
 *        |__|  |_| |_|  |__|   |___||____||____|/____/
 */

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

#define nmax 200020
#define ii pair<int, int>
#define ll long long

int n, k, ans, h[nmax][2], l[nmax], cnt[1000100], sz[nmax], r[nmax];
vector<ii> adj[nmax];

inline bool minimize(int &a, int b)
{
    return (a == -1 || a > b) ? a = b, 1 : 0;
}

int dfs(int u, int p = -1)
{
    sz[u] = 1;
    for(auto [C, v]: adj[u]) {
        if(v != p && !r[v]) sz[u] += dfs(v, u);
    }
    return sz[u];
}

int get_centroid(int m, int u, int p = -1)
{
    for(auto [C, v]: adj[u]) {
        if(v != p && !r[v] && 2 * sz[v] > m) return get_centroid(m, v, u);
    }
    return u;
}

void get_cnt(int sum, bool filling, int u, int p = -1, int depth = 1)
{
    if(sum > k) return;
    if(filling)
        minimize(cnt[sum], depth);
    else {
        if(~cnt[k - sum])
            minimize(ans, depth + cnt[k - sum]);
    }
    for(auto [C, v]: adj[u]) {
        if(v != p && !r[v]) get_cnt(sum + C, filling, v, u, depth + 1);
    }
}

void del(int sum, int u, int p = -1)
{
    if(sum > k) return;
    cnt[sum] = -1;
    for(auto [C, v]: adj[u]) {
        if(v != p && !r[v])
            del(sum + C, v, u);
    }
}

void centroid(int u = 0)
{
    u = get_centroid(dfs(u), u);
    r[u] = 1;
    cnt[0] = 0;
    for(auto [C, v]: adj[u]) {
        get_cnt(C, false, v);
        get_cnt(C, true, v);
    }
    for(auto [C, v]: adj[u]) {
        del(C, v);
    }
    for(auto [C, v]: adj[u]) {
        if(!r[v]) centroid(v);
    }
}

int best_path(int n, int k, int h[][2], int l[])
{
    for(int i = 0, u, v; i < n - 1; ++i) {
        u = h[i][0];
        v = h[i][1];
        adj[u].push_back(ii(l[i], v));
        adj[v].push_back(ii(l[i], u));
    }
    ans = -1;
    memset(cnt, -1, sizeof(cnt));
    centroid();
    return ans;
}

/* void solve()
 * {
 *     cin >> n >> k;
 *     for(int i = 0; i < n - 1; ++i) {
 *         cin >> h[i][0] >> h[i][1] >> l[i];
 *     }
 *     cout << best_path(n, k, h, l) << '\n';
 * }
 *
 * int main()
 * {
 *     ios::sync_with_stdio(false); cin.tie(NULL);
 * //    freopen("in.inp", "r", stdin);
 * //    freopen("out.out", "w", stdout);
 * //    freopen("err.txt", "w", stderr);
 *     int T;
 *     for(T = 1; T--;) {
 *         solve();
 *     }
 *     return 0;
 * }
 */

컴파일 시 표준 에러 (stderr) 메시지

race.cpp: In function 'int dfs(int, int)':
race.cpp:29:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   29 |     for(auto [C, v]: adj[u]) {
      |              ^
race.cpp: In function 'int get_centroid(int, int, int)':
race.cpp:37:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   37 |     for(auto [C, v]: adj[u]) {
      |              ^
race.cpp: In function 'void get_cnt(int, bool, int, int, int)':
race.cpp:52:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   52 |     for(auto [C, v]: adj[u]) {
      |              ^
race.cpp: In function 'void del(int, int, int)':
race.cpp:61:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   61 |     for(auto [C, v]: adj[u]) {
      |              ^
race.cpp: In function 'void centroid(int)':
race.cpp:72:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   72 |     for(auto [C, v]: adj[u]) {
      |              ^
race.cpp:76:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   76 |     for(auto [C, v]: adj[u]) {
      |              ^
race.cpp:79:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   79 |     for(auto [C, v]: adj[u]) {
      |              ^

• Subtask 1: 0 / 9
• Subtask 2: 0 / 12
• Subtask 3: 0 / 22
• Subtask 4: 0 / 57