Submission #320772

#	Time	Username	Problem	Language	Result	Execution time	Memory
320772		MiricaMatei	Zagrade (COI20_zagrade)	C++14	100 / 100	1987 ms	2112 KiB

zagrade

#include <bits/stdc++.h>

using namespace std;

const int MAXN =  100005;

int stk[MAXN], top;

int q(int a, int b) {
  cout << '?' << ' ' << a << ' ' << b << endl;
  int x;
  cin >> x;
  return x;
}

int main() {
  int n, m;
  cin >> n >> m;
  string s;
  for (int i = 1; i <= n; ++i) {
    s = s + ' ';
    if (top == 0 || !q(stk[top], i)) {
      stk[++top] = i;
    } else {
      s[stk[top--] - 1] = '(';
      s[i - 1] = ')';
    }
  }

  for (int i = 1; i <= top / 2; ++i)
    s[stk[i] - 1] = ')';
  for (int i = top / 2 + 1; i <= top; ++i)
    s[stk[i] - 1] = '(';

  cout << '!' << ' ' << s;

  return 0;
}

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