A bracket is considered to be any one of the following characters: (
, )
, {
, }
, [
, or ]
.
Two brackets are considered to be a matched pair if the an opening bracket (i.e., (
, [
, or {
) occurs to the left of a closing bracket (i.e., )
, ]
, or }
) of the exact same type. There are three types of matched pairs of brackets: []
, {}
, and ()
.
A matching pair of brackets is not balanced if the set of brackets it encloses are not matched. For example, {[(])}
is not balanced because the contents in between {
and }
are not balanced. The pair of square brackets encloses a single, unbalanced opening bracket, (
, and the pair of parentheses encloses a single, unbalanced closing square bracket, ]
.
Some examples of balanced brackets are []{}()
, [({})]{}()
and ({(){}[]})[]
.
By this logic, we say a sequence of brackets is considered to be balanced if the following conditions are met:
- It contains no unmatched brackets.
- The subset of brackets enclosed within the confines of a matched pair of brackets is also a matched pair of brackets.
Given strings of brackets, determine whether each sequence of brackets is balanced. If a string is balanced, print YES
on a new line; otherwise, print NO
on a new line.
Input Format
The first line contains a single integer, , denoting the number of strings.
Each line of the subsequent lines consists of a single string, , denoting a sequence of brackets.
Constraints
- , where is the length of the sequence.
- Each character in the sequence will be a bracket (i.e.,
{
,}
,(
,)
,[
, and]
).
Output Format
For each string, print whether or not the string of brackets is balanced on a new line. If the brackets are balanced, print YES
; otherwise, print NO
.
Sample Input
3
{[()]}
{[(])}
{{[[(())]]}}
Sample Output
YES
NO
YES
Explanation
- The string
{[()]}
meets both criteria for being a balanced string, so we printYES
on a new line. - The string
{[(])}
is not balanced, because the brackets enclosed by the matched pairs[(]
and(])
are not balanced. Thus, we printNO
on a new line. - The string
{{[[(())]]}}
meets both criteria for being a balanced string, so we printYES
on a new line.
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