Submission #1057967

#	Time	Username	Problem	Language	Result	Execution time	Memory
1057967		Dan4Life	Rarest Insects (IOI22_insects)	C++17	25 / 100	2346 ms	218872 KiB

insects

#include "insects.h"
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) begin(a), end(a)
using vi = vector<int>;
using ll = long long;
using ar2 = array<ll,2>;
using ar3 = array<ll,3>;
const int mxN = (int)2e3+10;
int n, cnt[mxN];
vi v, others;
set<int> S;
map<set<int>,int> M;

bool move_in(int i){
	if(S.count(i)) return 0;
	S.insert(i); move_inside(i);
	return 1;
}

bool move_out(int i){
	if(!S.count(i)) return 0;
	S.erase(i); move_outside(i);
	return 1;
}

int press(){
	if(sz(S)==1) return 1;
	if(M.count(S)) return M[S];
	return M[S] = press_button(); 
}

int min_cardinality(int N) {
	n = N; int ans = n, D=n;
	vector<int> xd(n,0); iota(all(xd),0);
	random_shuffle(all(xd));
	for(int i = 0; i < n; i++){
		move_in(xd[i]);
		if(press()==2) move_out(xd[i]), D--;
	}
	for(int i = 0; i < n; i++) move_out(xd[i]);
	int l = 1, r = n;
	while(l<r){
		int mid = (l+r+1)/2, tot=n;
		vi undo; undo.clear();
		for(int i = 0; i < n; i++){
			if(!move_in(xd[i])) continue;
			if(press()>mid) move_out(xd[i]), tot--;
			else undo.pb(xd[i]);
		}
		if(tot==D*mid) l = mid;
		else{
			for(auto u : undo) move_out(u);
			r=mid-1;
		}
	}
	return l;
}

Compilation message (stderr)

insects.cpp: In function 'int min_cardinality(int)':
insects.cpp:36:13: warning: unused variable 'ans' [-Wunused-variable]
   36 |  n = N; int ans = n, D=n;
      |             ^~~

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 0 / 75