Submission #668506

#	Time	Username	Problem	Language	Result	Execution time	Memory
668506		hoanghq2004	Rarest Insects (IOI22_insects)	C++17	57.92 / 100	154 ms	560 KiB

insects

#include <bits/stdc++.h>
#pragma GCC optimize ("O3")
#pragma GCC optimize ("unroll-loops")
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include "insects.h"

using namespace __gnu_pbds;
using namespace std;

template <typename T>
using ordered_set = tree <T, null_type, less <T>, rb_tree_tag, tree_order_statistics_node_update>;


//
//static inline constexpr int kMaxQueries = 40000;
//
//static int N;
//// Insect types are compressed to colors in the range [0, N).
//static std::vector<int> color;
//static std::vector<bool> in_box;
//
//static std::vector<int> color_occurrences;
//static std::multiset<int> max_occurrences;
//
//static std::vector<int> op_counter(3, 0);
//
//static inline void protocol_violation(std::string message) {
//  printf("Protocol Violation: %s\n", message.c_str());
//  exit(0);
//}
//
//void move_inside(int i) {
//  if (i < 0 || i >= N) {
//    protocol_violation("invalid parameter");
//  }
//  ++op_counter[0];
//  if (op_counter[0] > kMaxQueries) {
//    protocol_violation("too many calls");
//  }
//  if (!in_box[i]) {
//    in_box[i] = true;
//    max_occurrences.erase(max_occurrences.find(color_occurrences[color[i]]));
//    ++color_occurrences[color[i]];
//    max_occurrences.insert(color_occurrences[color[i]]);
//  }
//}
//
//void move_outside(int i) {
//  if (i < 0 || i >= N) {
//    protocol_violation("invalid parameter");
//  }
//  ++op_counter[1];
//  if (op_counter[1] > kMaxQueries) {
//    protocol_violation("too many calls");
//  }
//  if (in_box[i]) {
//    in_box[i] = false;
//    max_occurrences.erase(max_occurrences.find(color_occurrences[color[i]]));
//    --color_occurrences[color[i]];
//    max_occurrences.insert(color_occurrences[color[i]]);
//  }
//}
//
//int press_button() {
//  ++op_counter[2];
//  if (op_counter[2] > kMaxQueries) {
//    protocol_violation("too many calls");
//  }
//  return *(max_occurrences.rbegin());
//}

int min_cardinality(int n) {
    vector <int> s, root(n);
    for (int i = 0; i < n; ++i) {
        move_inside(i);
        if (press_button() == 1) s.push_back(i), ++root[i];
        else move_outside(i);
    }
    vector <int> a;
    for (int i = 0; i < n; ++i) if (!root[i]) a.push_back(i);
    function <void(int, int, vector <int>)> divide = [&](int L, int R, vector <int> a) {
        if (L > R || a.empty()) return;
        if (L == R) {
            for (auto x: a) ++root[s[L]];
            return;
        }
        int mid = L + R >> 1;
        for (int i = mid + 1; i <= R; ++i) move_outside(s[i]);
        vector <int> l, r;
        for (auto x: a) {
            move_inside(x);
            if (press_button() > 1) l.push_back(x);
            else r.push_back(x);
            move_outside(x);
        }
        divide(L, mid, l);
        for (int i = mid + 1; i <= R; ++i) move_inside(s[i]);
        divide(mid + 1, R, r);
    };
    divide(0, s.size() - 1, a);
    int ans = n;
    for (int i = 0; i < n; ++i)
        if (root[i]) ans = min(ans, root[i]);
    return ans;
}

//
//int main() {
//  assert(1 == scanf("%d", &N));
//  color.resize(N);
//  in_box.assign(N, false);
//
//  std::map<int, int> type_to_color;
//  for (int i = 0; i < N; ++i) {
//    int Ti;
//    assert(1 == scanf("%d", &Ti));
//    if (type_to_color.find(Ti) == type_to_color.end()) {
//      int new_color = type_to_color.size();
//      type_to_color[Ti] = new_color;
//      max_occurrences.insert(0);
//    }
//    color[i] = type_to_color[Ti];
//  }
//
//  color_occurrences.assign(type_to_color.size(), 0);
//
//  int answer = min_cardinality(N);
//  int Q = *std::max_element(op_counter.begin(), op_counter.end());
//  printf("%d\n", answer);
//  printf("%d\n", Q);
//  return 0;
//}

Compilation message (stderr)

insects.cpp: In lambda function:
insects.cpp:85:23: warning: unused variable 'x' [-Wunused-variable]
   85 |             for (auto x: a) ++root[s[L]];
      |                       ^
insects.cpp:88:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   88 |         int mid = L + R >> 1;
      |                   ~~^~~

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 32.92 / 75