제출 #970000

#제출 시각아이디문제언어결과실행 시간메모리
970000Ghetto경주 (Race) (IOI11_race)C++17
컴파일 에러
0 ms0 KiB
#include <bits/stdc++.h> using namespace std; using lint = long long; using pil = pair<int, lint>; using pli = pair<lint, int>; using mli = unordered_map<lint, int>; const int MAX_N = 2e5 + 5, INF = 2e9; int n; lint k; vector<pil> adj[MAX_N]; bool del[MAX_N]; int sub_size[MAX_N]; void upd_sizes(int u, int par = -1) { sub_size[u] = 1; for (pil x : adj[u]) { int v = x.first; if (v == par || del[v]) continue; upd_sizes(v, u); sub_size[u] += sub_size[v]; } } int find_cent(int u, int tot_size, int par = -1) { for (pil x : adj[u]) { int v = x.first; if (v == par || del[v]) continue; if (sub_size[v] * 2 > tot_size) return find_cent(v, tot_size, u); } return u; } mli lens[MAX_N], pref_lens; void merge(mli& x, mli& y) { // y into x if (x.size() < y.size()) x.swap(y); for (pli z : y) x[z.first] = x.count(z.first) ? min(x[z.first], z.second) : z.second; } void upd_lens(int u, int par, lint dist, int depth = 1) { lens[u].insert({dist, depth}); for (pil x : adj[u]) { int v = x.first; if (v == par || del[v]) continue; upd_lens(v, u, dist + x.second, depth + 1); merge(lens[u], lens[v]); } } int ans = INF; void build(int u) { upd_sizes(u); int cent = find_cent(u, sub_size[u]); pref_lens.clear(); for (pil x : adj[cent]) if (!del[x.first]) lens[x.first].clear(); for (pil x : adj[cent]) { int v = x.first; if (del[v]) continue; upd_lens(v, cent, x.second); for (pli y : lens[v]) { if (y.first == k) ans = min(ans, y.second); else if (pref_lens.count(k - y.first)) ans = min(ans, y.second + pref_lens[k - y.first]); } merge(pref_lens, lens[v]); } del[cent] = true; for (pil x : adj[cent]) if (!del[x.first]) build(x.first); } int main() { freopen("race.in", "r", stdin); freopen("race.out", "w", stdout); cin.sync_with_stdio(false); cin.tie(0); cin >> n >> k; for (int i = 1; i < n; i++) { int u, v; cin >> u >> v; lint w; cin >> w; adj[u].push_back({v, w}); adj[v].push_back({u, w}); } build(0); if (ans == INF) ans = -1; cout << ans << '\n'; }

컴파일 시 표준 에러 (stderr) 메시지

race.cpp: In function 'int main()':
race.cpp:70:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   70 |     freopen("race.in", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
race.cpp:71:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   71 |     freopen("race.out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/ccudlUH8.o: in function `main':
race.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccKbOYV5.o:grader.cpp:(.text.startup+0x0): first defined here
/usr/bin/ld: /tmp/ccKbOYV5.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