Submission #486992

#	Time	Username	Problem	Language	Result	Execution time	Memory
486992		noob_c0de	Race (IOI11_race)	C++14	Compilation error	0 ms	0 KiB

race

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define ar array
#define db double
#define sz(x) (int)x.size()
#define mat vector<vector<int> >
const db pi = acos(-1);
const int mxn = 2e5 + 7, INF = 1e6 + 7;;
int n, k, ans;
vector<ar<int, 2> > g[mxn];
int depth[mxn], len[mxn];
map<int, int> mp[mxn];
int r[mxn];
// int h[mxn][2];
// int l[mxn];
void dfs(int u, int p)
{
    for (auto [v, w] : g[u])
    {
        if (v == p) continue;
        depth[v] = depth[u] + 1;
        len[v] = len[u] + w;
        dfs(v, u);
    }
}
void gopset(int u, int v)
{
    if (sz(mp[r[u]]) < sz(mp[r[v]])) swap(r[u], r[v]);
    for (auto it = mp[r[v]].begin(); it != mp[r[v]].end(); it++)
    {
        int t = it->first, dep = it->second;
        if (mp[r[u]].count(k - t + 2 * len[u]))
        {
            ans = min(ans, mp[r[u]][k - t + 2 * len[u]] + dep - 2 * depth[u]);
        }
    }
    for (auto it = mp[r[v]].begin(); it != mp[r[v]].end(); it++)
    {
        int t = it->first, dep = it->second;
        if (mp[r[u]].count(t)) mp[r[u]][t] = min(mp[r[u]][t], dep);
        else mp[r[u]][t] = dep;   
    }
}
void dfs2(int u, int p)
{
    mp[u][len[u]] = depth[u];
    for (auto [v, w] : g[u])
    {
        if (v == p) continue;
        dfs2(v, u);
        gopset(u, v);
    }
}
int best_path(int n, int k, int h[][2], int l[])
{
    for (int i = 0; i < n; i++)
    {
        g[h[i][0]].push_back({h[i][1], l[i]});
        g[h[i][1]].push_back({h[i][0], l[i]});
    }
    for (int i = 0; i < n; i++) r[i] = i;
    dfs(0, 0);
    ans = INF; 
    dfs2(0, 0);
    if (ans == INF) return -1;
    return ans;
}
// signed main()
// {
//     ios::sync_with_stdio(0);
//     cin.tie(0); cout.tie(0);
//     // De nghi ko bat ultra instinct tay nhanh hon nao luc lam bai
//     cin >> n >> k;
//     for (int i = 0; i < n - 1; i++) cin >> h[i][0] >> h[i][1];
//     for (int i = 0; i < n - 1; i++) cin >> l[i];
//     int res = best_path(n, k, h, l);
//     if (res == INF) cout << -1;
//     else cout << res;
//     return 0;
// }

Compilation message (stderr)

race.cpp: In function 'void dfs(long long int, long long int)':
race.cpp:19:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   19 |     for (auto [v, w] : g[u])
      |               ^
race.cpp: In function 'void dfs2(long long int, long long int)':
race.cpp:48:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   48 |     for (auto [v, w] : g[u])
      |               ^
/usr/bin/ld: /tmp/ccbZrOYi.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