제출 #897640

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
897640		Essa2006	버섯 세기 (IOI20_mushrooms)	C++14	25 / 100	34 ms	1048 KiB

mushrooms

#include<bits/stdc++.h>
using namespace std;
#define ll long long 
#define endl '\n'
#define FF first
#define SS second
#define all(a) a.begin(), a.end()
#define mod (ll)(1000000007)
#include "mushrooms.h"

//int cnt = 0;
//
//vector<int> B;
//
//int use_machine(vector<int> X) {
//    cnt++;
//    int res = 0;
//    for (int i = 1; i < X.size(); i++) {
//        if (B[X[i]] != B[X[i - 1]]) {
//            res++;
//        }
//    }   
//    return res;
//}

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

int count_mushrooms(int n) {
    
	vector<int> A(n);
    vector<int> Z = {0}, O;
    for (int i = 0; i < n; i++) {
        A[i] = i;
    }
    shuffle(A.begin() + 1, A.end(), rng);
    
    int ans = 1;
    
    int fir, sec;
    
    int cur = use_machine({A[0], A[1]});
    
    if (cur) {
        O.push_back(A[1]);
    }   
    else{
        Z.push_back(A[1]);
        ans++;
    }
    
    if (n == 2)
        return ans;
    
    int cur2 = use_machine({A[0], A[2]});
    
    if (cur2) {
        O.push_back(A[2]);
    }   
    else{
        Z.push_back(A[2]);
        ans++;
    }
    int i = 3;
    while (i < n - 1) {
        int j = i;
        vector<int>Ask;
        if (Z.size() > O.size()) {
            while (j < n){
                Ask.push_back(A[j]);
                if (Z.size() < j - i + 1 || j == n - 1) {
                    j++;
                    break;
                }
                Ask.push_back(Z[j - i]);
                j++;
            }
            int diff = use_machine(Ask);
            int all = (Ask.size() + 1) / 2;
            if (diff & 1) {
                int Bs = (diff + 1) / 2;
                ans += all - Bs;
            }
            else {
                int diff2 = use_machine({Z.front(), A[i]});
                if (diff2) {
                    O.push_back(A[i]);
                    O.push_back(A[j - 1]);
                    ans += all - (diff + 2)/ 2;
                }
                else {
                    Z.push_back(A[i]);
                    Z.push_back(A[j - 1]);
                    ans += all - diff / 2;
                }
            }
        }
        
        else {
            while (j < n){
                Ask.push_back(A[j]);
                if (O.size() < j - i + 1 || j == n - 1) {
                    j++;
                    break;
                }
                Ask.push_back(O[j - i]);
                j++;
            }
            int diff = use_machine(Ask);
            int all = (Ask.size() + 1) / 2;
            if (diff & 1) {
                int As = (diff + 1) / 2;
                ans += As;
            }
            else {
                int diff2 = use_machine({O.front(), A[i]});
                if (diff2) {
                    Z.push_back(A[i]);
                    Z.push_back(A[j - 1]);
                    ans += (diff / 2 + 1);
                }
                else {
                    O.push_back(A[i]);
                    O.push_back(A[j - 1]);
                    ans += diff / 2;
                }
            }
        }
        
        i = j;
    }
    if (i == n - 1) {
        int diff = use_machine({Z.front(), A[i]});
        ans += 1 - diff;   
    }
    return ans;
}

//int main() {
//    int n, m;
//    cin >> n >> m;
//    
//    int mx = 0;
//    for (int times = 0; times < m; times++) {
//        B.clear();
//        B.resize(n);
//        
//        cnt = 0;
//        for (int i = 0; i < n; i++) {
//            B[i] = rng() % 2;
//        }
//
//        int res = count_mushrooms(n);
//        mx = max(mx, cnt);
//    }
//    cout << mx;
//}

컴파일 시 표준 에러 (stderr) 메시지

mushrooms.cpp: In function 'int count_mushrooms(int)':
mushrooms.cpp:70:30: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   70 |                 if (Z.size() < j - i + 1 || j == n - 1) {
      |                     ~~~~~~~~~^~~~~~~~~~~
mushrooms.cpp:101:30: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  101 |                 if (O.size() < j - i + 1 || j == n - 1) {
      |                     ~~~~~~~~~^~~~~~~~~~~
mushrooms.cpp:109:17: warning: unused variable 'all' [-Wunused-variable]
  109 |             int all = (Ask.size() + 1) / 2;
      |                 ^~~
mushrooms.cpp:39:9: warning: unused variable 'fir' [-Wunused-variable]
   39 |     int fir, sec;
      |         ^~~
mushrooms.cpp:39:14: warning: unused variable 'sec' [-Wunused-variable]
   39 |     int fir, sec;
      |              ^~~

• Subtask 1: 25 / 100