# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
329648 | GioChkhaidze | Zagrade (COI20_zagrade) | C++14 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
char C_[500005];
int n_,x_,pr_[500005],nx_[500005];
int main () {
cin>>n_>>q_; // ;(((((((((((((((((((((((((((((( qqqqqqq
for (int i=1; i<=n_+3; i++)
nx_[i]=i+1,pr_[i]=i-1,C_[i]='.';
int l_=1,r_=2,L_=l_,R_=r_,ans_=n_/2;
while (1<=L_ && L_<=n_ && 1<=R_ && R_<=n_ && L_<=R_) {
l_=L_,r_=R_;
cout<<"? "<<l_<<" "<<r_<<endl;
cin>>x_;
if (x_) {
--ans_;
C_[l_]='(',C_[r_]=')';
if (nx_[r_]>n_) break;
if (1<=pr_[l_]) {
L_=pr_[l_];
R_=nx_[r_];
nx_[L_]=R_;
pr_[R_]=L_;
}
else {
if (nx_[nx_[r_]]>n_) break;
L_=nx_[r_],R_=nx_[nx_[r_]];
pr_[L_]=0;
}
}
else {
if (nx_[r_]>n_) break;
assert(nx_[l_]==r_);
L_=nx_[l_],R_=nx_[r_];
pr_[L_]=l_;
nx_[L_]=R_;
pr_[R_]=L_;
}
}
for (int i=1; i<=n_; i++)
if (C_[i]=='.') {
if (ans_>0)
C_[i]=')',--ans_;
else
C_[i]='(';
}
cout<<"! ";
for (int i=1; i<=n_; i++)
cout<<C_[i];
cout<<endl;
}