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#257 Longest Balanced Bracket Stretch

hard

A code editor highlights the longest stretch of a line that is made of balanced parentheses. A stretch is balanced when every ( in it is closed by a later ) in it, in the usual nested way, such as (())().

Write longestBalanced(text) that takes a string of only ( and ) and returns the length of its longest balanced substring (a run of neighboring characters). Return 0 if there is none.

Example 1

Input: text = "(()"
Output: 2

The longest balanced stretch is ().

Example 2

Input: text = ")()())"
Output: 4

()() in the middle has length 4.

Constraints

  • 0 <= text.length <= 3 * 10^4
  • text has only ( and ).
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Run tries your code on the examples. Submit runs every test, including hidden edge cases, and solves the problem when they all pass.

Ctrl + Enter runs, Ctrl + Shift + Enter submits (⌘ on a Mac).