Submission #492701

#	Time	Username	Problem	Language	Result	Execution time	Memory
492701		zhougz	Colors (BOI20_colors)	C++17	0 / 100	1 ms	200 KiB

Colors

    /**
     *    author: chowgz
     *    created: 13/04/2021 20:13:22
    **/
    #include <bits/stdc++.h>
     
    using namespace std;
     
    int main() {
    	ios::sync_with_stdio(false);
    	cin.tie(0);
    	int tt;
    	cin >> tt;
    	while (tt--) {
    		long long n;
    		cin >> n;
    		long long l = 1, r = n - 1, m = (l + r) / 2;
    		stack<long long> s;
    		while (m != n - 1) {
    			m = (l + r) / 2;
    			s.push(m);
    			l = m + 1;
    		}
    		long long cur = n;
    		bool up = false;
    		while (!s.empty()) {
    			cur += up ? s.top() : -s.top();
    			up = !up;
    			s.pop();
    		}
    		bool yes;
    		auto ask = [&](long long x) {
    			cur += up ? x : -x;
    			up = !up;
    			cout << "? " << cur << endl;
              cout.flush();
    			cin >> yes;
    		};
    		cout << "? " << cur << endl;
          cout.flush();
    		cin >> yes;
    		l = 1;
    		r = n - 1;
    		m = (l + r) / 2;
    		long long ans = n;
    		while (l <= r) {
    			ask(m);
    			if (yes) {
    				ans = m;
    				r = m - 1;
    			} else {
    				l = m + 1;
    			}
    			m = (l + r) / 2;
    		}
    		cout << "= " << ans << endl;
          cout.flush();
    	}
    	return 0;
    }

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