Submission #1198671

#	Time	Username	Problem	Language	Result	Execution time	Memory
1198671		sheercold	9월 (APIO24_september)	C++20	0 / 100	1 ms	324 KiB

september

#include <bits/stdc++.h>

using namespace std;

using i64 = long long;

int solve(int n, int m, std::vector<int> p,
          std::vector<std::vector<int>> s) {
  mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
  vector<vector<int>> tree(n);
  for (int i = 1; i < n; i++) {
    tree[p[i]].push_back(i);
  }
  vector<int> mx(n);
  for (int i = 0; i < m; i++) {
    for (int j = 0; j < n - 1; j++) {
      mx[s[i][j]] = max(mx[s[i][j]], j);
    }
  }
  auto dfs = [&](auto&& self, int v) {
    for (int nxt : tree[v]) {
      if (nxt == p[v]) {
        continue;
      }
      self(self, nxt);
      mx[v] = max(mx[v], mx[nxt]);
    }
  };
  vector<int> R(n - 1);
  iota(R.begin(), R.end(), 0);
  for (int i = 0; i < m; i++) {
    for (int j = 0; j < n - 1; j++) {
      R[j] = max(R[j], mx[s[i][j]]);
    }
  }
  vector<int> v(n - 1, 1);
  for (int iter = 0; iter < 30; iter++) {
    vector<int> hash(n);
    for (int i = 0; i < n; i++) {
      hash[i] = rng();
    }
    vector<int> pref(m);
    for (int i = 0; i < n - 1; i++) {
      for (int j = 0; j < m; j++) {
        pref[j] ^= hash[s[j][i]];
      }
      int valid = 1;
      for (int j = 1; j < m; j++) {
        valid &= pref[j] == pref[j - 1];
      }
      v[i] &= valid;
    }
  }
  int ans = 0;
  for (int i = 0, r = 0; i < n - 1; i++) {
    r = max(r, R[i]);
    if (r <= i && v[i]) {
      ++ans;
    }
  }
  return ans;
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 14
• Subtask 3: 0 / 5
• Subtask 4: 0 / 9
• Subtask 5: 0 / 5
• Subtask 6: 0 / 11
• Subtask 7: 0 / 9
• Subtask 8: 0 / 11
• Subtask 9: 0 / 9
• Subtask 10: 0 / 16