Submission #1137412

#TimeUsernameProblemLanguageResultExecution timeMemory
1137412JeffLegendPowerRace (IOI11_race)C++20
43 / 100
296 ms86576 KiB
// https://oj.uz/problem/view/IOI11_race #include <bits/stdc++.h> #include <ext/pb_ds/assoc_container.hpp> #include <ext/pb_ds/tree_policy.hpp> using namespace __gnu_pbds; using namespace std; #define ll long long #define plli pair<ll, int> #define pll pair<ll, ll> #define pii pair<int, int> // Usage: FOR(i, 0, N) {...} #define FOR(i, start, end) for(int i = start; i < end; i++) mt19937 rng(chrono::steady_clock::now().time_since_epoch().count()); int uid(int a, int b) { return uniform_int_distribution<int>(a, b)(rng); } ll uld(ll a, ll b) { return uniform_int_distribution<ll>(a, b)(rng); } void setIO(string s) { freopen((s + ".in").c_str(), "r", stdin); freopen((s + ".out").c_str(), "w", stdout); } struct comp { bool operator() (const plli& a, const plli& b) const { return a < b; } }; typedef tree<plli, null_type, comp, rb_tree_tag, tree_order_statistics_node_update> ordered_multiset; // Segtree start const int Nmax = 1e5; // limit for array size int N; // array size int t[2 * Nmax]; int oper(int a, int b) { return a + b; } void build() { // build the tree for (int i = N - 1; i > 0; --i) t[i] = oper(t[i<<1], t[i<<1|1]); } void modify(int p, int value) { // set value at position p for (t[p += N] = value; p > 1; p >>= 1) t[p>>1] = oper(t[p], t[p^1]); } int query(int l, int r) { // on interval [l, r) int res = 0; for (l += N, r += N; l < r; l >>= 1, r >>= 1) { if (l&1) res = oper(res, t[l++]); if (r&1) res = oper(res, t[--r]); } return res; } // Segtree end const int MAXN = 2e5; struct node { vector<plli> next; ll dist = 0; int dep = 0; }; node graph[MAXN]; set<plli> dists[MAXN]; int mindist = 1e8; void dfs(int v, int p, ll K) { for (auto [w, x] : graph[v].next) { if (x == p) continue; graph[x].dist = graph[v].dist + w; graph[x].dep = graph[v].dep + 1; dfs(x, v, K); } dists[v].insert({graph[v].dist, graph[v].dep}); for (auto [w, x] : graph[v].next) { if (x == p) continue; if (dists[x].size() > dists[v].size()) swap(dists[x], dists[v]); for (auto [dist, dep] : dists[x]) { ll target = K + 2*graph[v].dist - dist; auto itr = dists[v].lower_bound({target, 0}); if (itr != dists[v].end() && itr->first == target) { mindist = min(mindist, dep + itr->second - 2*graph[v].dep); } dists[v].insert({dist, dep}); } } } int best_path(int N, int K, int H[][2], int L[]) { for (int i = 0; i < N-1; i++) { auto [u, v] = H[i]; ll w = L[i]; graph[u].next.push_back({w, v}); graph[v].next.push_back({w, u}); } dfs(0, -1, K); return (mindist == 1e8 ? -1 : mindist); } // int main() { // // Comment out for interactive problems // ios::sync_with_stdio(false); // cin.tie(nullptr); // int N; // ll K; // cin >> N >> K; // int H[N-1][2]; // ll 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); // }

Compilation message (stderr)

race.cpp: In function 'void setIO(std::string)':
race.cpp:22:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   22 |         freopen((s + ".in").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
race.cpp:23:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   23 |         freopen((s + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...
#Verdict Execution timeMemoryGrader output
Fetching results...