Submission #1189128

#	Time	Username	Problem	Language	Result	Execution time	Memory
1189128		vito	Mađioničar (COI22_madionicar)	C++20	13 / 100	460 ms	432 KiB

Main

#include <bits/stdc++.h>
using namespace std;
using ll=long long;
#define F first
#define S second
#define sz(x) int(x.size())
signed main() {
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	int n;
	cin >> n;
	int l=0, r=n/2+1, m;
	while(l+1<r) {
		m=(l+r)/2;
		int L=m*2;
		if(L>n) {
			r=m;
			continue;
		}
		int ok=0;
		for(int i=1; i<=n-L+1; i++) {
			cout << "? " << i << ' ' << i+L-1 << '\n';
			cout.flush();
			int x;
			cin >> x;
			if(x) {
				ok=1;
				break;
			}
		}
		if(ok) {
			l=m;
		}
		else {
			r=m;
		}
	}
	int out=2*l;
	l=0, r=n/2+1;
	while(l+1<r) {
		m=(l+r)/2;
		int L=m*2+1;
		if(L>n) {
			r=m;
			continue;
		}
		int ok=0;
		for(int i=1; i<=n-L+1; i++) {
			cout << "? " << i << ' ' << i+L-1 << '\n';
			cout.flush();
			int x;
			cin >> x;
			if(x) {
				ok=1;
				break;
			}
		}
		if(ok) {
			l=m;
		}
		else {
			r=m;
		}
	}
	out=max(out, 2*l+1);
	cout << "! " << out << '\n';
	cout.flush();
	return 0;
}

• Subtask 1: 13 / 13
• Subtask 2: 0 / 25
• Subtask 3: 0 / 25
• Subtask 4: 0 / 37