This is my final project in theory of languages . This context-free automaton accepts strings in which number of 'a' characters are as the same of number of 'b' characters and in every prefix of the string, number of 'a' characters are more than 'b' characters.
Its grammer is as follows:
we can also give an arethmetic expression to this automaton and it shows us if the equal string of that expression is accepted or not.