201412: [AtCoder]ARC141 C - Bracket and Permutation
Description
Score : $600$ points
Problem Statement
A string of length $2N$, $S=S_1S_2\dots S_{2N}$, is said to be a parenthesis sequence when $S$ is composed of $N$ (
s and $N$ )
s.
Additionally, a parenthesis sequence $S$ is said to be correct when it is one of the following.
- An empty string.
- The concatenation of
(
, $A$,)
in this order, where $A$ is a correct parenthesis sequence. - The concatenation of $A$, $B$ in this order, where $A$ and $B$ are non-empty correct parenthesis sequences.
You are given two permutations $P=(P_1,\ P_2,\ \dots,\ P_{2N})$ and $Q=(Q_1,\ Q_2,\ \dots,\ Q_{2N})$ of the integers from $1$ to $2N$.
Determine whether there exists a parenthesis sequence $S=S_1S_2\dots S_{2N}$ that satisfies the following conditions.
- $P$ is the lexicographically smallest permutation $p$ of the integers from $1$ to $2N$ such that $S_{p_1}S_{p_2}\dots S_{p_{2N}}$ is a correct parenthesis sequence.
- $Q$ is the lexicographically largest permutation $p$ of the integers from $1$ to $2N$ such that $S_{p_1}S_{p_2}\dots S_{p_{2N}}$ is a correct parenthesis sequence.
If such a parenthesis sequence exists, find one.
Constraints
- $1 \leq N \leq 2 \times 10^5$
- $1 \leq P_i,Q_i \leq 2N$
- Each of $P$ and $Q$ is a permutation of $1$ to $2N$.
- All values in input are integers.
Input
Input is given from Standard Input in the following format:
$N$ $P_1$ $P_2$ $\dots$ $P_{2N}$ $Q_1$ $Q_2$ $\dots$ $Q_{2N}$
Output
If there exists a parenthesis sequence $S$ that satisfies the conditions above, print one such sequence. If there are multiple such sequences, you may print any of them.
If there is no such sequence, print -1
.
Sample Input 1
2 1 2 4 3 4 3 1 2
Sample Output 1
())(
For $S=$ ())(
, some of the permutations $p$ such that $S_{p_1}S_{p_2}S_{p_3}S_{p_4}$ is a correct parenthesis sequence are $p=(1,\ 4,\ 2,\ 3),\ (1,\ 4,\ 3,\ 2)$. The lexicographically smallest and largest among them are $p=(1,\ 2,\ 4,\ 3)$ and $p=(4,\ 3,\ 1,\ 2)$, satisfying the conditions.
Sample Input 2
2 1 3 2 4 4 3 2 1
Sample Output 2
-1
No $S$ satisfies the conditions.
Sample Input 3
3 2 1 5 3 4 6 6 5 3 4 2 1
Sample Output 3
-1