Submission #773476

#	Time	Username	Problem	Language	Result	Execution time	Memory
773476		vjudge1	Zagrade (COI20_zagrade)	C++17	100 / 100	835 ms	900 KiB

zagrade

#include <bits/stdc++.h>
using namespace std;

void f(){
	freopen("in.txt", "r", stdin);
	freopen("out.txt", "w", stdout);
}

int qu(int a, int b){
	cout<<"? "<<a+1<<" "<<b+1<<endl;
	cin>>a; return a;	
}

void solve(){
	int n, m; cin >> n >> m;

	string s;
	stack<int> q;

	for(int i=0; i < n; i++) s+='.';

	q.push(0);

	for(int i=1; i<n; i++){
		if(!q.size()){
			q.push(i);
		}
		else if(qu(q.top(), i)){
			s[q.top()]='(';
			s[i]=')';
			q.pop();
		}
		else{
			q.push(i);
		}
	}

	int p=q.size()/2;
	while(p--){
		s[q.top()]='(';
		q.pop();
	}

	while(q.size()){
		s[q.top()]=')';
		q.pop();
	}

	cout<<"! "<<s<<endl;

}
int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(0);


	solve();
}

Compilation message (stderr)

zagrade.cpp: In function 'void f()':
zagrade.cpp:5:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 |  freopen("in.txt", "r", stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
zagrade.cpp:6:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    6 |  freopen("out.txt", "w", stdout);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

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