title: Develop Turing Machine to count number of As and Bs in a String
body: <p>The given Language is 
  L = {a^n b^n where n>= 0}
  I have to develop a turing machine for it but i dont get the logic. will it go like this if an a is not followed by a b you go to halt reject state, but how we check if the count of a and b are equal?
  will be very grateful for any response</p>