Competitions
Stack Data Structure
Bracket sequence
The bracket sequence is a correct arithmetic expression, from which all numbers and signs are removed. For example,
1 + ( ( ( 2 + 3 ) + 5 ) + ( 3 + 4 ) ) → ( ( ( ) ) ( ) )
Input
A sequence of opening and closing brackets is given. The length of the sequence is no more than 4000000.
Output
Print "YES" if the bracket sequence is correct and "NO" otherwise.
Input example #1
((())())
Output example #1
YES
Input example #2
(()
Output example #2
NO