Nesting

nesting.rb

require "rspec"

def nesting(string)
  opens = 0
  string.each_char do |c| 
    case c
    when "(" then opens += 1
    when ")" then opens > 0 ? (opens -= 1) : (return 0)
    end 
  end
  opens == 0 ? 1 : 0  
end

describe "nesting" do 
 before do 
  @a =  "(()(())sdf())()()()((((abc))))(()())((lkjsdf()()()))(()()(()))"
  @b =  ")(()(())())()()()(((())))(()())((()()()))(()()(()))("
 end
  
  it "should be 1 with a" do 
    nesting(@a).should eq 1
  end
  
  it "should be 0 with b" do 
    nesting(@b).should eq 0
  end
end