Submission #750041

#	Time	Username	Problem	Language	Result	Execution time	Memory
750041		vjudge1	Carnival (CEOI14_carnival)	C++14	0 / 100	0 ms	208 KiB

carnival

#include <bits/stdc++.h>
#define ii pair<int,int>
#define f first
#define s second
#define pb push_back
#define int long long
#define endl '\n'
using namespace std;
const int MAXN = 1e18;
int mod = 1e9 + 7;
struct data
{
	int a,b,c;
	string s;
};
int ask(int l,int r)
{
	cout << "? " << l << " " << r << endl;
	int res;
	cin >> res;
	return res;
}
void AcSolution()
{
	int n;
	cin >> n;
	int l = 1;
	int r = n;
	while(l < r)
	{
		if(r - l == 1)
		{
			int ans1 = ask(l,r);
			if(ans1 == r)
			{
				cout << "! " << l << endl;
			}
			else
			{
				cout << "! " << r << endl; 
			}
			return;
		}
		int mid = (l + r) / 2;
		int ans1 = ask(l,r);
		if(ans1 < mid)
		{
			int ans2 = ask(l,mid);
			if(ans2 == ans1)
			{
				r = mid;
			}
			else
			{
				l = mid + 1;
			}
		}
		else
		{
			int ans2 = ask(mid,r);
			if(ans2 == ans1)
			{
				l = mid;
			}
			else
			{
				r = mid - 1;
			}
		}
	}
	cout << "! " << l << endl;
}
signed main()
{
	int t = 1;
//	cin >> t;
	while(t--)
	{
	 	AcSolution();
	}
}

• Subtask 1: 0 / 20
• Subtask 2: 0 / 20
• Subtask 3: 0 / 20
• Subtask 4: 0 / 20
• Subtask 5: 0 / 20