JFLAP Turing Machine shortcut problem
- by Robert Lamb
In JFLAP (http://jflap.org), there are some shortcuts for Turing machine transitions. One of these shortcuts allows you to transition as long as the current tape symbol isn't the indicated symbol. For example, the transition !g,x;R basically says "Take this transition if the current tape symbol is not g".
So far, so good. But the transition I want is !?,~;R which basically says "Move right as long as the current symbol is not the end-of-string (empty cell) symbol". The problem is I cannot figure out how to type in "!?".
The JFLAP online documentation (http://www.jflap.org/tutorial/turing/one/index.html#syntax) has this to say:
The first shortcut is that there exists the option of using
the “!” character to convey the meaning of “any character
but this character.” For example, concerning the transition
(!a; x, R), if the head encounters any character but an “a”,
it will replace the character with an “x” and move right.
To write the expression “!?”, just type a “1” in when inputting
a command.
My question is...how do I actually do what that last sentence is trying to explain to me?
Thanks for your help!
Robert
