제출 #1123426

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1123426		LucaLucaM	9월 (APIO24_september)	C++20	100 / 100	235 ms	11456 KiB

september

#include "september.h"

#include <vector>
#include <algorithm>
#include <iostream>
#include <random>

std::mt19937 rng(123);

#define debug(x) #x << " = " << x << '\n'

int solve(int n, int m, std::vector<int> parent, std::vector<std::vector<int>> s) {
	std::vector<bool> ok(n - 1, true);
  std::vector<std::vector<int>> g(n);
  for (int i = 1; i < n; i++) {
    g[parent[i]].push_back(i);
    g[i].push_back(parent[i]);
  }
  std::vector<int> rnd(n);
  for (int i = 0; i < n; i++) {
    rnd[i] = rng();
  }
  std::vector<int> hsh(n, -1);
  for (const auto &a : s) {
    std::vector<bool> alive(n, true);
    int cur = n - 1;
    int me = 0;
    for (int i = 0; i < n - 1; i++) {
      // daca sterg nodurile 0..i atunci cate noduri u am a.i. si u si parent[u] sunt vii?
      int u = a[i];
      me ^= rnd[u];
      if (hsh[i] == -1) {
        hsh[i] = me;
      } else {
        if (hsh[i] != me) {
          ok[i] = false;
        }
      }
      // std::cout << debug(u) << ' ' << debug(parent[u]);
      for (const auto &v : g[u]) {
        if (alive[v]) {
          cur--;
        }
      }
      alive[u] = false;
      if (cur != n - 2 - i) {
        ok[i] = false;
      }
    }
  }

  return std::count(ok.begin(), ok.end(), true);
}

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