Submission #708804

#	Time	Username	Problem	Language	Result	Execution time	Memory
708804		t6twotwo	Rarest Insects (IOI22_insects)	C++17	100 / 100	87 ms	304 KiB

insects

#include "insects.h"
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int min_cardinality(int n) {
    vector<bool> in(n);
    for (int i = 0; i < n; i++) {
        move_inside(i);
        if (press_button() == 2) move_outside(i);
        else in[i] = 1;
    }
    int type = 0;
    vector<bool> blocked(n);
    for (int i = 0; i < n; i++) {
        if (in[i]) {
            type++;
            blocked[i] = 1;
        }
    }
    int lo = 1, hi = n / type, cnt = type;
    while (lo < hi) {
        int x = (lo + hi + 1) / 2;
        vector<int> p(n);
        iota(p.begin(), p.end(), 0);
        random_shuffle(p.begin(), p.end());
        for (int i = 0; i < n; i++) {
            if (blocked[p[i]] || cnt == x * type) continue;
            move_inside(p[i]);
            if (press_button() == x + 1) move_outside(p[i]);
            else in[p[i]] = 1, cnt++;
        }
        int t = cnt;
        for (int i = 0; i < n; i++) {
            if (blocked[i]) continue;
            if (in[i]) {
                if (t == x * type) {
                    blocked[i] = 1;
                } else {
                    in[i] = 0;
                    cnt--;
                    move_outside(i);
                }
            } else if (t != x * type) {
                blocked[i] = 1;
            }
        }
        if (t == x * type) lo = x;
        else hi = t / type;
    }
    return lo;
}

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