제출 #1262949

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1262949		kawhiet	경주 (Race) (IOI11_race)	C++20	0 / 100	1 ms	320 KiB

race

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

vector<vector<pair<int, int>>> g;
vector<map<int, int>> dp;

int k, res;

void dfs(int u, int p) {
    dp[u][0] = 0;
    for (auto [v, w] : g[u]) {
        if (v == p) continue;
        dp[u][w] = 1;
        dfs(v, u);
        if (dp[v].size() > dp[u].size()) {
            swap(dp[v], dp[u]);
        }
        map<int, int> new_dp = dp[u];
        for (auto [x, c] : dp[u]) {
            for (auto [y, d] : dp[v]) {
                if (x == y) {
                    new_dp[x] = min(c, d);
                }
                if (!new_dp.count(y)) {
                    new_dp[y] = d;
                }
                else {
                    new_dp[y] = min(new_dp[y], d);
                }
                if (!new_dp.count(x + y)) {
                    new_dp[x + y] = c + d;
                }
                else {
                    new_dp[x + y] = min(new_dp[x + y], c + d);
                }
            }
        }
        swap(dp[u], new_dp);
    }
    if (dp[u].count(k)) {
        res = min(res, dp[u][k]);
    }
}

int best_path(int N, int K, int H[][2], int L[]) {
    k = K;
    g.resize(N);
    dp.resize(N);
    for (int i = 0; i < N - 1; i++) {
        int u = H[i][0], v = H[i][1], w = L[i];
        g[u].push_back({v, w});
        g[v].push_back({u, w});
    }
    res = N + 1;
    dfs(0, -1);
    return (res == N + 1 ? -1 : res);
}

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