Submission #1151132

#	Time	Username	Problem	Language	Result	Execution time	Memory
1151132		emptypringlescan	Colors (BOI20_colors)	C++20	100 / 100	1 ms	408 KiB

Colors

#include <bits/stdc++.h>
using namespace std;

int32_t main(){
    //ios::sync_with_stdio(0);
    //cin.tie(0);
    long long n;
    cin >> n;
    long long cur=1,smol=1,big=1;
    long long lo=1,hi=n,mid;
    while(lo<hi){
		mid=(lo+hi)/2ll;
		if(cur>1) cur-=mid;
		else cur+=mid;
		lo=mid+1;
		smol=min(smol,cur);
		big=max(big,cur);
	}
	cur=2-smol;
	//cout << smol << ' ' << big << '\n';
	lo=1,hi=n;
	cout << "? " << cur << endl;
	int x;
	cin >> x;
	long long dir=1;
	bool prev=true;
	while(lo<hi){
		if(prev||lo==hi-1ll) mid=(lo+hi)/2ll;
		else mid=(lo+hi+1ll)/2ll;
		cur+=mid*dir;
		dir*=-1ll;
		cout << "? " << cur << endl;
		cin >> x;
		if(x) hi=mid,prev=false;
		else lo=mid+1ll,prev=true;
	}
	cout << "= " << lo << endl;
}

• Subtask 1: 9 / 9
• Subtask 2: 13 / 13
• Subtask 3: 21 / 21
• Subtask 4: 24 / 24
• Subtask 5: 33 / 33