Submission #1129961

#	Time	Username	Problem	Language	Result	Execution time	Memory
1129961		vladilius	Colors (BOI20_colors)	C++20	0 / 100	0 ms	432 KiB

Colors

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define pb push_back
#define ff first
#define ss second

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    
    int n; cin>>n;
    
    auto ask = [&](int x){
        cout<<"? "<<x<<"\n";
        cout.flush();
        bool t; cin>>t;
        return t;
    };
    
    auto check = [&](int x){
        if (x == n){
            ask(1);
            return !ask(n);
        }
        ask(1);
        return ask(x + 1);
    };
    
    int l = 1, r = n;
    while (l + 1 < r){
        int m = (l + r) / 2;
        if (check(m)){
            r = m;
        }
        else {
            l = m + 1;
        }
    }
    
    if (check(l)) r = l;
    
    cout<<"= "<<r<<"\n";
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 13
• Subtask 3: 0 / 21
• Subtask 4: 0 / 24
• Subtask 5: 0 / 33