Submission #675905

#	Time	Username	Problem	Language	Result	Execution time	Memory
675905		VodkaInTheJar	Counting Mushrooms (IOI20_mushrooms)	C++14	86.59 / 100	8 ms	348 KiB

mushrooms

#include <bits/stdc++.h>

using namespace std;

const int c = 50; 

int use_machine(vector <int> x);
int count_mushrooms(int n) {
    vector <int> as;
    vector <int> bs;

    as.push_back(0);

    if (n >= 200) {
    if (use_machine({0, 1}) == 1)
        bs.push_back(1);

    else 
        as.push_back(1);

    if (use_machine({0, 2}) == 1)
        bs.push_back(2);

    else 
        as.push_back(2);

    for (int i = 3; i <= c; i += 2) {
        if ((int)as.size() >= 2) {
            int cnt_bs = use_machine({as[0], i, as[1], i + 1});
            if (cnt_bs == 3) {
                bs.push_back(i);
                bs.push_back(i+1);
            }

            else 
                if (cnt_bs == 2) {
                    bs.push_back(i);
                    as.push_back(i+1);
                }

                else 
                    if (cnt_bs == 1) {
                        bs.push_back(i+1);
                        as.push_back(i);
                    }

                    else {
                        as.push_back(i);
                        as.push_back(i+1);
                    }
        }

        else {
            int cnt_as = use_machine({bs[0], i, bs[1], i + 1});
            if (cnt_as == 3) {
                as.push_back(i);
                as.push_back(i+1);
            }

            else 
                if (cnt_as == 2) {
                    bs.push_back(i+1);
                    as.push_back(i);
                }

                else 
                    if (cnt_as == 1) {
                        bs.push_back(i);
                        as.push_back(i+1);
                    }

                    else {
                        bs.push_back(i);
                        bs.push_back(i+1);
                    }
        }
    }
    }

    int pos = c + 1, ans = (int)as.size();
    if (n < 200)
        pos = 1;

    while (pos < n) {
        if ((int)as.size() >= (int)bs.size()) {
            int nxt = min(n, pos + (int)as.size());
            vector <int> temp;
            for (int i = pos; i < nxt; i++) {
                temp.push_back(as[i-pos]);
                temp.push_back(i);
            }

            int cnt_b = use_machine(temp);
            if (cnt_b & 1)
                bs.push_back(nxt-1), ans += (int)temp.size() / 2 - (cnt_b + 1) / 2;
            
            else 
                as.push_back(nxt-1), ans += (int)temp.size() / 2 - cnt_b / 2;
        
            pos = nxt; 
        }

        else {
            int nxt = min(n, pos + (int)bs.size());
            vector <int> temp;
            for (int i = pos; i < nxt; i++) {
                temp.push_back(bs[i-pos]);
                temp.push_back(i);
            }

            int cnt_a = use_machine(temp);
            if (cnt_a & 1)
                as.push_back(nxt-1), ans += (cnt_a + 1) / 2;
            
            else 
                bs.push_back(nxt-1), ans += cnt_a / 2;
        
            pos = nxt; 
        }
    }

    return ans;
}

• Subtask 1: 86.59 / 100