Submission #631786

#	Time	Username	Problem	Language	Result	Execution time	Memory
631786		garam1732	Rarest Insects (IOI22_insects)	C++17	96.10 / 100	73 ms	620 KiB

insects

#include "insects.h"
#include <iostream>
#include <vector>
#include <stack>
#include <set>
#include <algorithm>
#include <cassert>
#define ff first
#define ss second
using namespace std;
typedef pair<int, int> pi;

//vector<int> ans;
//stack<pi> S, v;
vector<int> v, w, u[2020];
set<int> s;

int min_cardinality(int N) {
//    v.clear(); w.clear(); s.clear();
//    for(int i = 0; i < 2020; i++) u[i].clear();

    int num = 0;
    for(int i = 0; i < N; i++) {
        move_inside(i);
        num++;
        if(press_button() > 1) {
            move_outside(i);
            num--;
            s.insert(i);
        }
    }

    //cout<<num<<endl;
    int sum = num;
    int lb = 1, ub = N, mid;
    while(lb < ub) {
        mid = lb+ub+1>>1;
        for(int i : s) {
            move_inside(i);
            int x = press_button();
            if(x > mid) {
                w.push_back(i);
                move_outside(i);
                continue;
            }
            u[x].push_back(i);
            sum++;
        }

        bool flag = false;
        while(lb < ub) {
            mid = lb+ub+1>>1;

//            for(int i = lb; i <= ub+1; i++) {
//                cout<<i<<" : ";
//                for(int t:u[i])cout<<t<<" ";
//                cout<<endl;
//            }
//            cout<<endl;
            if(flag) {
                for(int i = ub+1; i > mid; i--) {
                    for(int t : u[i]) {
                        move_outside(t);
                        sum--;
                    }
                }

                //assert(press_button() == mid);
                for(int i = mid+1; i <= ub+1; i++) {
                    for(int t : u[i]) {
                        move_inside(t);
                        if(press_button() > mid) {
                            move_outside(t);
                            w.push_back(t);
                        }
                        else {
                            sum++;
                            u[mid].push_back(t);
                        }
                    }
                }
            }
            flag = true;
            //cout<<sum<<endl;

            if(sum == mid*num) {
                for(int i = lb+1; i <= mid; i++)
                    for(int t : u[i])
                        s.erase(t);
                for(int i = lb+1; i <= ub+1; i++) u[i].clear();
                lb = mid;
                w.clear();
                break;
            }
            else {
                for(int t : w) s.erase(t);
//                for(int t : u[mid]) move_outside(t);
//                sum -= u[mid].size();
                for(int i = mid+1; i <= ub+1; i++) u[i].clear();
                w.clear();
                ub = mid-1;
            }
        }
    }

    return lb;
}

Compilation message (stderr)

insects.cpp: In function 'int min_cardinality(int)':
insects.cpp:37:20: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   37 |         mid = lb+ub+1>>1;
      |               ~~~~~^~
insects.cpp:52:24: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   52 |             mid = lb+ub+1>>1;
      |                   ~~~~~^~

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 71.1 / 75