Submission #957843

#	Time	Username	Problem	Language	Result	Execution time	Memory
957843		MisterReaper	Race (IOI11_race)	C++17	Compilation error	0 ms	0 KiB

race

#include <bits/stdc++.h>
using i64 = long long;

constexpr int maxN = 2E5 + 5;

int n, k;
std::map<i64, int> s[maxN];
std::vector<std::pair<int, int>> adj[maxN];
int h[maxN], d[maxN];
int ans = maxN;

void dfs(int node, int par) {
    for(auto [child, w] : adj[node]) {
        if(child == par) {
            continue;
        }
        h[child] = h[node] + w;
        d[child] = d[node] + 1;
        dfs(child, node);
    }
    return;
}

void s2l(int node, int par) {
    i64 target = k + h[node] * 2;
    s[node][h[node]] = d[node];
    for(auto [child, w] : adj[node]) {
        if(child == par) {
            continue;
        }
        s2l(child, node);
        if(s[child].size() > s[node].size()) {
            std::swap(s[child], s[node]);
        }

        for(auto [a, b] : s[child]) {
            if(s[node].count(target - a)) {
                ans = std::min(ans, s[node][target - a] + b - 2 * d[node]);
            }
        }

        for(auto [a, b] : s[child]) {
            if(!s[node].count(a)) {
                s[node][a] = n;
            }
            s[node][a] = std::min(s[node][a], b);
        }
    }

    /*
    std::cerr << "node: " << node << "\n";
    for(auto [a, b] : s[node]) {
        std::cerr << a << " " << b << "\n";
    }
    */
}

int bestpath(int N, int K, int H[][2], int L[]) {
    n = N;
    k = K;
    for(int i = 0; i < n - 1; i++) {
        //std::cerr << H[i][0] << " " << H[i][1] << " :: " << L[i] << "\n";
        adj[H[i][0]].emplace_back(H[i][1], L[i]);
        adj[H[i][1]].emplace_back(H[i][0], L[i]);
    }

    dfs(0, -1);
    s2l(0, -1);

    if(ans == maxN) {
        ans = -1;
    }
    return ans;
}

Compilation message (stderr)

/usr/bin/ld: /tmp/ccsQ2Wp6.o: in function `main':
grader.cpp:(.text.startup+0x28): undefined reference to `best_path(int, int, int (*) [2], int*)'
collect2: error: ld returned 1 exit status