Submission #780922

#	Time	Username	Problem	Language	Result	Execution time	Memory
780922		christinelynn	Zagrade (COI20_zagrade)	C++17	100 / 100	757 ms	860 KiB

zagrade

#include<bits/stdc++.h>
using namespace std;
bool ask(int l, int r) {
  if((r-l)&1^1) return 0;
  cout << "? " << l << ' ' << r << endl;
  bool ret; cin >> ret;
  return ret;
}
int main() {
  ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  int n, q; cin >> n >> q;
  stack<int> J;
  string s;
  for(int i=0; i<n; i++) s+='-';
  for(int i=0; i<n; i++) {
    if(J.empty()) J.push(i);
    else {
      if(ask(J.top()+1, i+1)) s[J.top()]='(', s[i]=')', J.pop();
      else J.push(i);
    }
  }
  int sz=(int)J.size() >> 1;
  while(!J.empty()) {
    if(sz) s[J.top()]='(', sz--;
    else s[J.top()]=')';
    J.pop();
  }
  cout << "! " << s << '\n';
  return 0;
}

Compilation message (stderr)

zagrade.cpp: In function 'bool ask(int, int)':
zagrade.cpp:4:11: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
    4 |   if((r-l)&1^1) return 0;
      |      ~~~~~^~

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