#include <bits/stdc++.h> using namespace std; using ll = long long; vector<vector<pair<ll, int>>> g; vector<bool> dead; vector<int> subtree_size; int ans = INT_MAX; void compute_subtree_size(int u, int p) { subtree_size[u] = 1; for (auto[w, v] : g[u]) { if (v == p || dead[v]) continue; compute_subtree_size(v, u); subtree_size[u] += subtree_size[v]; } } int find_centroid(int u, int p) { int mx_val = 0, mx_node = 0; for (auto[w, v] : g[u]) { if (v == p || dead[v]) continue; if (subtree_size[v] > mx_val) { mx_val = subtree_size[v]; mx_node = v; } } if (mx_val <= (g.size()-1)/2) return u; else find_centroid(mx_node, u); } unordered_map<ll, int> mp; vector<pair<ll, int>> vals; void dfs(int u, int p, ll dist, int path) { vals.push_back({dist, path}); for (auto[w, v] : g[u]) { if (v == p || dead[v]) continue; dfs(v, u, dist+w, path+1); } } int ans = INT_MAX; void decompose(int u, ll K) { compute_subtree_size(u, 0); int centroid = find_centroid(u, 0); for (auto[w, v] : g[centroid]) { if (dead[v]) continue; dfs(v, centroid, w, 1); for (auto vals_i : vals) if (mp.count(K-vals_i.first)) ans = min(ans, vals_i.second + mp[vals_i.first]); for (auto vals_i : vals) mp[vals_i.first] = min(mp[vals_i.first], vals_i.second); vals.clear(); } if (mp.count(K)) ans = min(ans, mp[K]); mp.clear(); dead[centroid] = true; for (auto[w, v] : g[centroid]) { if (dead[v]) continue; decompose(v, K); } } int best_path(int N, ll K, int H[][2], ll L[]) { g = vector<vector<pair<ll, int>>>(N+1); for (int i = 0; i < N-1; i++) { g[H[i][0]].push_back({L[i], H[i][1]}); g[H[i][1]].push_back({L[i], H[i][0]}); } }

race.cpp:58:5: error: redefinition of 'int ans'
   58 | int ans = INT_MAX;
      |     ^~~
race.cpp:8:5: note: 'int ans' previously defined here
    8 | int ans = INT_MAX;
      |     ^~~
race.cpp: In function 'int best_path(int, ll, int (*)[2], ll*)':
race.cpp:104:1: warning: no return statement in function returning non-void [-Wreturn-type]
  104 | }
      | ^
race.cpp: In function 'int find_centroid(int, int)':
race.cpp:41:22: warning: control reaches end of non-void function [-Wreturn-type]
   41 |         find_centroid(mx_node, u);
      |         ~~~~~~~~~~~~~^~~~~~~~~~~~