Submission #957800

#	Time	Username	Problem	Language	Result	Execution time	Memory
957800		Trisanu_Das	Race (IOI11_race)	C++17	Compilation error	0 ms	0 KiB

race

#include <bits/stdc++.h>
#include "race.h"
using namespace std;
#define ff first
#define ss second

vector<pair<int, int> > adj[200005];
map<int, int> sum_to_dist[200005];
int sum[200005], dist[200005], N, K, ans;

void dfs(int u, int p, int s, int d){
  sum_to_dist[u][s] = d;
  sum[u] = s;
  dist[u] = d;
  for(auto v : adj[u]) if(v.ff != p) dfs(v.ff, u, s + v.ss, d + 1);
}

void merge_dfs(int u, int p){
  int target = k + 2 * sum[u];
  for(auto v : adj[u]){
    if(v.ff == p) continue;
    merge_dfs(v.ff, u);
    if(sum_to_dist[v.ff].size() > sum_to_dist[u].size()) swap(sum_to_dist[v.ff], sum_to_dist[u]);
    for(auto p : sum_to_dist[v.ff]) if(sum_to_dist[u].find(target - p.ff) != sum_to_dist[u].end()) ans = min(ans, sum_to_dist[u][target - p.ff] + p.ss - 2 * dist[u]);
    for(auto p : sum_to_dist[v.ff]){
      if(sum_to_dist[u].find(p.ff) == sum_to_dist[u].end()) sum_to_dist[u].insert(p);
      else sum_to_dist[u][p.ff] = min(sum_to_dist[u][p.ff], p.ss);
    }
  }
}

int best_path(int n, int k, int h[][2], int l[]){
  N = n; K = k;
  for(int i = 0; i < n - 1; i++){
    int u = h[i][0], v = h[i][1], w = l[i];
    adj[u].push_back({v, w});
    adj[v].push_back({u, w});
  }
  dfs(0, -1, 0, 0);
  merge_dfs(0, -1);
  return ans == INT_MAX ? -1 : ans;
}

Compilation message (stderr)

race.cpp: In function 'void merge_dfs(int, int)':
race.cpp:19:16: error: 'k' was not declared in this scope
   19 |   int target = k + 2 * sum[u];
      |                ^