Submission #1166553

#	Time	Username	Problem	Language	Result	Execution time	Memory
1166553		akamizane	Race (IOI11_race)	C++20	Compilation error	0 ms	0 KiB

race

#include<bits/stdc++.h>

using namespace std;

#define int long long
using ll = long long;

const int maxn = 2e5 + 5;

map<int,int> info[maxn];
int d[maxn], sum[maxn];
vector<pair<int,int>> ad[maxn];
int N, K, res;

void pre(int u, int p, int val, int h){
  info[u][val] = h;
  sum[u] = val;
  d[u] = h;
  for (auto [v, w] : ad[u]){
    if (v == p) continue;
    pre(v, u, val + w, h + 1);
  }
}

void dfs(int u, int p){
  int need = K + 2 * sum[u];
  for (auto [v, w] : ad[u]){
    if (v == p) continue;
    dfs(v, u);
    if (info[u].size() < info[v].size()){
      swap(info[u], info[v]);
    }
    for (auto [val, h] : info[v]){
      if (info[u].find(need - val) != info[u].end() ){
        res = min(res, info[u][need - val] + h - 2 * d[u]);
      }
    }
    for (auto [val, h] : info[v]){
      if (info[u].find(val) == info[u].end()){
        info[u][val] = h;
      }
      else info[u][val] = min(info[u][val], h);
    }
  }
}

int best_path(int n, int k, int edges[][2], int weights[]) {
  if (k == 1) { return 0; }
  N = n;
  K = k;
  res = INT_MAX;
  for (int i = 0; i < n - 1; i++) {
    int u = edges[i][0];
    int v = edges[i][1];
    ad[u].push_back(make_pair(v, weights[i]));
    ad[v].push_back(make_pair(u, weights[i]));
  }
  pre(0, -1, 0, 0);
  dfs(0, -1);
  return res == INT_MAX ? -1 : res;
}

Compilation message (stderr)

/usr/bin/ld: /tmp/ccAhVX9k.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