Submission #1262513

#	Time	Username	Problem	Language	Result	Execution time	Memory
1262513		kawhiet	Race (IOI11_race)	C++20	9 / 100	87 ms	50500 KiB

race

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

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

int k;

void dfs(int u, int p) {
    dp[u][0] = 0;
    for (auto [v, w] : g[u]) {
        if (v == p) continue;
        dfs(v, u);
        for (int i = w; i <= k; i++) {
            dp[u][i] = min(dp[u][i], dp[v][i - w] + 1);
        }
    }
}

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

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