Write program to simulate a dpda. the dpda specification is read from a text file (see sample on next page). the letters e and y are reserved for ε and ∅ , respectively. the program displays alphabet is: [[the alphabet of the dfa]] enter string. user enters the string the program verifies that the string is legal (if not, outputs a message informing the user and asking to input a legal string). it simulates the dpda on the input string and displays each move it makes (including the contents of the stack) in a convenient format. finally, it determines whether the string is accepted or rejected by the dpda; and displays the string [[user’s string]] is (not) accepted