Merge pull request #40 from christianbender/changed_balanced_parenthesis

simplified the function balanced_parentheses?

Author: sagivo

src/balanced_parentheses.rb

@@ -5,7 +5,9 @@ def balanced_parentheses?(str)
  when '('
  stack.push '('
  when ')'
- if stack.empty? || stack.pop != '('
+ if !stack.empty? 
+ stack.pop
+ else
  return false
  end
  end
@@ -15,3 +17,4 @@ def balanced_parentheses?(str)
 
 #test
 p balanced_parentheses? '( () ( () ) () )' # => true
+p balanced_parentheses? '(()' # => false