Submission #488276

#TimeUsernameProblemLanguageResultExecution timeMemory
488276SlavicGRace (IOI11_race)C++17
Compilation error
0 ms0 KiB
#include "bits/stdc++.h" using namespace std; #define ll long long #define forn(i,n) for(int i=0;i<n;i++) #define all(v) v.begin(), v.end() #define rall(v) v.rbegin(),v.rend() #define pb push_back #define sz(a) (int)a.size() const int N = 2e5 + 10; vector<pair<int, ll>> adj[N]; bool vis[N]; int s[N]; int K; map<ll, int> dp; void recalc(int u, int par){ s[u] = 1; for(auto x: adj[u]){ int v = x.first; if(v == par || vis[v])continue; recalc(v, u); s[u] += s[v]; } } int find_centroid(int u, int need, int par){ for(auto x: adj[u]){ int v = x.first; if(v == par || vis[v])continue; if(s[v] > need)return find_centroid(v, need, u); } return u; } int ans = INT_MAX; void dfs(int u, int par, ll weight, int type, int depth){ if(type == 0){ if(dp.count(K - weight)){ ans = min(ans, dp[K - weight] + depth); } } else{ if(!dp.count(weight))dp[weight] = depth; else dp[weight] = min(dp[weight], depth); } for(auto x: adj[u]){ int v = x.first, w = x.second; if(v == par || vis[v])continue; dfs(v, u, weight + w, type, depth + 1); } } void centroid_decomp(int u){ recalc(u, -1); int c = find_centroid(u, s[u] / 2, -1); vis[c] = true; dp.clear(); dp[0] = 0; for(auto x: adj[c]){ int v = x.first, w = x.second; if(vis[v])continue; dfs(v, -1, w, 0, 1); dfs(v, -1, w, 1, 1); } for(auto x: adj[c]){ int v = x.first; if(vis[v])continue; centroid_decomp(v); } } int best_path(int n, int k, vector<vector<int>> h, vector<int> l){ for(int i = 0;i < n - 1; ++i){ adj[h[i][0]].pb({h[i][1], l[i]}); adj[h[i][1]].pb({h[i][0], l[i]}); } centroid_decomp(0); if(ans == INT_MAX)return -1; return ans; } /* void solve() { int n, k; cin >> n >> k; K = k; vector<vector<int>> h(n - 1, vector<int>(2, 0)); vector<int> l(n - 1); 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]; } cout << best_path(n, k, h, l) << "\n"; } int32_t main(){ ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0); int t = 1; //cin >> t; while(t--) { solve(); } } */

Compilation message (stderr)

/usr/bin/ld: /tmp/ccFRkuDg.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