Submission #315651

#	Time	Username	Problem	Language	Result	Execution time	Memory
315651		Sorting	Counting Mushrooms (IOI20_mushrooms)	C++17	79.86 / 100	10 ms	384 KiB

mushrooms

#include "mushrooms.h"
#include <bits/stdc++.h>

using namespace std;

const int C = 283;

int count_mushrooms(int n){
    int cnt = 1;
    vector<int> a{0}, b;

    for(int i = 1; i < min(n, 3); ++i){
        if(!use_machine(vector<int>{0, i})){
            cnt++;
            a.push_back(i);
        }
        else b.push_back(i);
    }

    for(int i = 3; i < min(n, C + 1); i += 2){
        vector<int> v;
        bool which;
        if(a.size() >= 2){
            v = {a[0], a[1]};
            which = false;
        }
        else{
            v = {b[0], b[1]};
            which = true;
        }

        if(i == min(n, C + 1) - 1){
            if(!use_machine(vector<int>{0, i})){
                cnt++;
                a.push_back(i);
            }
            else b.push_back(i);
            break;
        }

        int t = use_machine({v[0], i, v[1], i + 1});
        if(!which) t = 3 - t;

        if(t & 2){
            cnt++;
            a.push_back(i);
        }
        else b.push_back(i);

        if(t & 1){
            cnt++;
            a.push_back(i + 1);
        }
        else b.push_back(i + 1);
    }

    for(int i = min(n, C + 1); i < n; i += (C / 2)){
        vector<int> v;
        int x = min(C / 2, n - i);
        if(a.size() > b.size()){
            for(int j = 0; j < x; ++j){
                v.push_back(a[j]);
                v.push_back(i + j);
            }
            v.push_back(a[x]);
        }
        else{
            for(int j = 0; j < x; ++j){
                v.push_back(b[j]);
                v.push_back(i + j);
            }
            v.push_back(b[x]);
        }

        int t = use_machine(v);
        if(a.size() > b.size()) cnt += x - t / 2;
        else cnt += t / 2;
    }

    return cnt;
}

• Subtask 1: 79.8587 / 100