Hi, here’s your problem today. This problem was recently asked by Twitter:

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Given a string with only ( and ), find the minimum number of characters to add or subtract to fix the string such that the brackets are balanced.

Example:

Input: '(()()'
Output: 1

Explanation:

The fixed string could either be ()() by deleting the first bracket, or (()()) by adding a bracket. These are not the only ways of fixing the string, there are many other ways by adding it in different positions!

Here’s some code to start with:

def fix_brackets(s):
  # Fill this in.

print fix_brackets('(()()')
# 1