Submission #648075

#	Time	Username	Problem	Language	Result	Execution time	Memory
648075		Kenpar	Guess the number (BOI20_guess)	C++17	100 / 100	1 ms	296 KiB

Guess

//CSES grind baby

#include "bits/stdc++.h"
using namespace std;
#define ll long long

const ll MOD = 1e9+7;
const ll INF = 1e16;
const ll MAX = 2e5+1;

int ask(int x){
	int temp;
	cout<<"? "<<x<<endl;

	cin>>temp;
	return temp;
}

int bSearch(int l, int r){
	if(r >= l){
		int mid = (l+r)>>1;

		int ans = ask(mid);

		if(ans == 0){
			return mid;
		}else if(ans > 0){
			return bSearch(l, mid-1);
		}

		return bSearch(mid+1, r);
	}else{
		cout<<1;
	}
}
void solve(){
	int n;
	cin>>n;

	int ans = bSearch(1,n);

	cout<<"= "<<ans;
}	


int main()
{
	//cin.tie(NULL);
	//ios::sync_with_stdio(NULL);
	int t = 1;

	//cin >> t;

	while(t--){
		solve();
		cout<<endl;
	}
}

Compilation message (stderr)

Guess.cpp: In function 'int bSearch(int, int)':
Guess.cpp:33:9: warning: control reaches end of non-void function [-Wreturn-type]
   33 |   cout<<1;
      |         ^

• Subtask 1: 29 / 29
• Subtask 2: 71 / 71