Submission #922676

#	Time	Username	Problem	Language	Result	Execution time	Memory
922676		hazzle	Jail (JOI22_jail)	C++17	61 / 100	5087 ms	36680 KiB

jail

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>

//#pragma GCC optimize("Ofast,unroll-loops")
//#pragma GCC target("avx,avx2,fma")

using namespace std;
using namespace __gnu_pbds;

#define fi first
#define se second
#define all(m) (m).begin(), (m).end()
#define rall(m) (m).rbegin(), (m).rend()
#define vec vector
#define sz(a) (int) (a).size()
#define mpp make_pair
#define mtt make_tuple

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
typedef pair <ll, ll> pll;
typedef pair <int, int> pii;
typedef tuple <int, int, int> tui;

template <typename T>
using prq = priority_queue <T>;

template <typename T>
using pgq = priority_queue <T, vec <T>, greater <T>>;

template <typename T> bool umin(T &a, T b) { return a > b ? a = b, 1 : 0; }
template <typename T> bool umax(T &a, T b) { return a < b ? a = b, 1 : 0; }

const int L = 17;

inline int solve(){
     int n; cin >> n;
     vec <vec <int>> g(n);
     for (int i = 0; i < n - 1; ++i){
          int u, v;
          cin >> u >> v, --u, --v;
          g[u].push_back(v);
          g[v].push_back(u);
     }
     vec <vec <int>> up(n, vec <int> (L));
     vec <int> fi(n), fo(n);
     int tmr = 0;
     auto dfs = [&](auto &&dfs, int u, int p) -> void{
          up[u][0] = p;
          for (int i = 1; i < L; ++i){
               up[u][i] = up[up[u][i - 1]][i - 1];
          }
          fi[u] = tmr++;
          for (auto &v: g[u]) if (v != p){
               dfs(dfs, v, u);
          }
          fo[u] = tmr;
     };
     dfs(dfs, 0, 0);
     auto par = [&](int u, int v){
          return fi[u] <= fi[v] && fo[v] <= fo[u];
     };
     auto lca = [&](int u, int v){
          if (par(u, v)) return u;
          if (par(v, u)) return v;
          for (int i = L - 1; ~i; --i){
               if (!par(up[u][i], v)) u = up[u][i];
          }
          return up[u][0];
     };
     auto on_path = [&](int u, int v, int w){
          return par(u, v) && par(v, w);
     };
     int m; cin >> m;
     vec <int> s(m), t(m), lc(m);
     for (int i = 0; i < m; ++i){
          cin >> s[i] >> t[i], --s[i], --t[i];
          lc[i] = lca(s[i], t[i]);
     }
     vec <int> deg(m);
     vec <vec <int>> gg(m);
     for (int i = 0; i < m; ++i){
          for (int j = 0; j < m; ++j){
               if (i == j) continue;
               if (on_path(lc[i], t[j], s[i]) || on_path(lc[i], t[j], t[i]) ||
                   on_path(lc[j], s[i], s[j]) || on_path(lc[j], s[i], t[j])){
                    gg[i].push_back(j);
                    ++deg[j];
               }
          }
     }
     vec <int> bfs;
     for (int i = 0; i < m; ++i){
          if (deg[i] == 0) bfs.push_back(i);
     }
     for (int pt = 0; pt < sz(bfs); ++pt){
          int u = bfs[pt];
          for (auto &v: gg[u]){
               if (--deg[v] == 0){
                    bfs.push_back(v);
               }
          }
     }
     cout << (sz(bfs) == m ? "Yes\n" : "No\n");
     return 0;
}

inline void precalc(){}

signed main(){
     ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
     int tst = 1; cin >> tst;
     precalc();
     while(tst--) solve();
     return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 5 / 5
• Subtask 3: 16 / 16
• Subtask 4: 28 / 28
• Subtask 5: 12 / 12
• Subtask 6: 0 / 11
• Subtask 7: 0 / 23