Submission #709636

#	Time	Username	Problem	Language	Result	Execution time	Memory
709636		therealpain	Crocodile's Underground City (IOI11_crocodile)	C++17	0 / 100	2 ms	2644 KiB

crocodile

#include "crocodile.h"
#include <bits/stdc++.h>

using namespace std;

const int N = 1e5 + 7;

vector <pair <int, int>> adj[N];
bool special[N];
int n, m, k;

namespace sub1 {
    long long dist[1000][1000];
    long long dp[1000][2];

    void dfs1(int u, int p, int root) {
        for (auto [v, w] : adj[u]) {
            if (v == p || v == root) continue;
            dist[root][v] = dist[root][u] + w;
            dfs1(v, u, root);
        }
    }

    void dfs2(int u, int p) {
        if (special[u] == true) {
            dp[u][0] = dp[u][1] = 0;
            return;
        }

        for (auto [v, w] : adj[u]) {
            if (v == p) continue;
            dfs2(v, u);
            if (dp[u][0] > dp[v][1] + w) {
                dp[u][1] = dp[u][0];
                dp[u][0] = dp[v][1] + w;
            } else if (dp[u][1] > dp[v][1] + w) {
                dp[u][1] = dp[v][1] + w;
            }
        }
    }

    long long solve() {
        for (int i = 0; i < n; ++i) {
            dfs1(i, i, i);
        }
        memset(dp, 0x3f, sizeof dp);
        dfs2(0, 0);
        return dp[0][1];
    }
};

int travel_plan(int N, int M, int R[][2], int L[], int K, int P[]) {
    n = N;
    m = M;
    k = K;
    for (int i = 0; i < m; ++i) {
        int u = R[i][0], v = R[i][1], w = L[i];
        adj[u].emplace_back(v, w);
        adj[v].emplace_back(u, w);
    }
    for (int i = 0; i < k; ++i) {
        int x; cin >> x;
        special[x] = true;
    }
    long long ans = sub1::solve();
    return ans;
}

• Subtask 1: 0 / 46
• Subtask 2: 0 / 43
• Subtask 3: 0 / 11