Submission #781283

#	Time	Username	Problem	Language	Result	Execution time	Memory
781283		devariaota	Zagrade (COI20_zagrade)	C++17	100 / 100	776 ms	1328 KiB

zagrade

#include <bits/stdc++.h>
#define int long long
#define pb push_back
#define pii pair<int, int>
#define fr first
#define sc second
#define query(l, r)                                                              cout << "? " << l << " " << r << endl;                                         cin >> res;
using namespace std;

const int N = 1e5 + 5;

string ans;
bool res;

signed main() {
    ios_base::sync_with_stdio(false);
    cout.tie(NULL);
    cin.tie(NULL);
    int n, q;
    cin >> n >> q;
    ans.assign(n, ' ');
    stack<int> s;
    s.push(1);
    int cnt = 0;
    for (int i = 2; i <= n; i++) {
        if (s.empty()) {
        s.push(i);
        continue;
        }
        int cur = s.top();
        query(cur, i);
        if (res) {
        ans[cur - 1] = '(';
        ans[i - 1] = ')';
        cnt++;
        s.pop();
        } else
        s.push(i);
    }
    int cntfrr = n / 2 - cnt;
    for (int i = 0; i < n; i++) {
        if (ans[i] == ' ') {
        if (cntfrr) {
            ans[i] = ')';
            cntfrr--;
        } else
            ans[i] = '(';
        }
    }
    cout << "! " << ans << endl;
}

• Subtask 1: 14 / 14
• Subtask 2: 7 / 7
• Subtask 3: 57 / 57
• Subtask 4: 22 / 22