Submission #1217376

#	Time	Username	Problem	Language	Result	Execution time	Memory
1217376		countless	Race (IOI11_race)	C++20	21 / 100	3094 ms	10492 KiB

race

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

typedef long long ll;
typedef long double ld;

#define sp <<" "<<
#define endl "\n"

int best_path(int N, int K, int H[][2], int L[]) {
    ll k = K;
    vector<vector<pair<int, ll>>> adj(N);
    for (int i = 0; i < N - 1; i++) {
        auto [u, v] = H[i];
        ll w = L[i];
        adj[u].push_back({v, w});
        adj[v].push_back({u, w});
    }

    vector<pair<ll, ll>> dist(N);

    auto dfs = [&](auto &&dfs, int u, int p = -1) -> void {
        for (auto &[v, w] : adj[u]) {
            if (v != p) {
                dist[v] = {dist[u].first + w, dist[u].second + 1};
                dfs(dfs, v, u);
            }
        }
    };

    ll best = LLONG_MAX;
    for (int i = 0; i < N; i++) {
        dist[i] = {0, 0};
        dfs(dfs, i);

        for (int j = 0; j < N; j++) {
            if (dist[j].first == k) {
                best = min(best, dist[j].second);
            }
        }
    }

    if (best == LLONG_MAX) best = -1;

    return best;
}

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