Submission #1119866

#	Time	Username	Problem	Language	Result	Execution time	Memory
1119866		btninh	Race (IOI11_race)	C++17	Compilation error	0 ms	0 KiB

race

#include <bits/stdc++.h>
#define int long long
#define N 100005
#define pb push_back
#define INF 1e18
using namespace std;

int sz[N], ans = INF, k;
bool vis[N];
map<int, int> cnt;
vector<pair<int, int>> g[N];

int dfs(int u, int p = -1) {
    sz[u] = 1;
    for (auto [v, w] : g[u]) {
        if (v != p && !vis[v]) {
            sz[u] += dfs(v, u);
        }
    }
    return sz[u];
}

int centroid(int u, int p, int len) {
    for (auto [v, w] : g[u]) {
        if (v != p && !vis[v] && sz[v] > len / 2) {
            return centroid(v, u, len);
        }
    }
    return u;
}

void calc(int u, int p, bool t, int sum, int d = 1) {
    if (t == 0) {
        if (!cnt[sum])
            cnt[sum] = d;
        else
            cnt[sum] = min(cnt[sum], d);
    } else {
        if (cnt[k - sum])
            ans = min(ans, d + cnt[k - sum]);
    }
    for (auto [v, w] : g[u]) {
        if (v != p && !vis[v]) {
            calc(v, u, t, sum + w, d + 1);
        }
    }
}

void solve(int u) {
    int c = centroid(u, -1, dfs(u));
    vis[c] = true;
    cnt.clear();
    cnt[0] = 0;
    for (auto [v, w] : g[c]) {
        if (!vis[v]) {
            calc(v, c, 1, w);
            calc(v, c, 0, w);
        }
    }
    for (auto [v, w] : g[c]) {
        if (!vis[v]) solve(v);
    }
}

void best_path(int n, int K, int roads[][2], int lengths[]) {
    k = K;
    for (int i = 0; i < n - 1; ++i) {
        int u = roads[i][0] + 1, v = roads[i][1] + 1;
        int l = lengths[i];
        g[u].pb({v, l});
        g[v].pb({u, l});
    }
    ans = INF;
    solve(1);
    cout << (ans != INF ? ans : -1) << "\n";
}

Compilation message (stderr)

/usr/bin/ld: /tmp/ccR4gApj.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