Submission #759786

#	Time	Username	Problem	Language	Result	Execution time	Memory
759786		MilosMilutinovic	Counting Mushrooms (IOI20_mushrooms)	C++14	92.24 / 100	11 ms	452 KiB

mushrooms

#include "mushrooms.h"
#include <bits/stdc++.h>
using namespace std;
const int C = 145;
int count_mushrooms(int n) {
    if (n <= 227) {
        int ans = 1;
        for (int i = 1; i < n; i++) {
            ans += !use_machine({0, i});
        }
        return ans;
    }
    vector<int> a(1, 0), b;
    for (int i = 1; i < min(n, C); i++) {
        if (a.size() >= 2) {
            int qq = use_machine({a[0], i, a[1], i + 1});
            if (qq & 1)
                b.push_back(i + 1);
            else
                a.push_back(i + 1);
            if (qq & 2)
                b.push_back(i);
            else
                a.push_back(i);
            i += 1;
            continue;
        }
        if (b.size() >= 2) {
            int qq = use_machine({b[0], i, b[1], i + 1});
            if (qq & 1)
                a.push_back(i + 1);
            else
                b.push_back(i + 1);
            if (qq & 2)
                a.push_back(i);
            else
                b.push_back(i);
            i += 1;
            continue;
        }
        if (use_machine({0, i}) == 1)
            b.push_back(i);
        else
            a.push_back(i);
    }
    sort(a.begin(), a.end());
    sort(b.begin(), b.end());
    int pos = 0;
    if (!a.empty())
        pos = max(pos, a.back());
    if (!b.empty())
        pos = max(pos, b.back());
    int ans = a.size();
    for (int i = pos + 1; i < n; i++) {
        int sz = max(a.size(), b.size());
        vector<int> qv;
        int cnt = 0;
        for (int j = i; j < min(i + sz, n); j++) {
            if (j != i + sz) {
                if (a.size() == sz)
                    qv.push_back(a[j - i]);
                else
                    qv.push_back(b[j - i]);
                cnt += 1;
            }
            qv.push_back(j);
        }
        int qq = use_machine(qv);
        int diff = (qq + 1) / 2;
        int same = (qv.size() - cnt  - diff);
        if (a.size() == sz)
            ans += same;
        else
            ans += diff;
        int is_match = (qq % 2 == 0 ? 1 : 0);
        if (a.size() != sz)
            is_match = 1 - is_match;
        if (is_match)
            a.push_back(qv.back());
        else
            b.push_back(qv.back());
        i = qv.back();
    }
    return ans;
}

Compilation message (stderr)

mushrooms.cpp: In function 'int count_mushrooms(int)':
mushrooms.cpp:60:30: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   60 |                 if (a.size() == sz)
      |                     ~~~~~~~~~^~~~~
mushrooms.cpp:71:22: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   71 |         if (a.size() == sz)
      |             ~~~~~~~~~^~~~~
mushrooms.cpp:76:22: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   76 |         if (a.size() != sz)
      |             ~~~~~~~~~^~~~~

• Subtask 1: 92.2449 / 100