Machine format

The transitions are entered as quintuples of the form State Sep Char Sep State Sep Char Sep Move where

• State can be any nonempty string of alphanumeric characters
• Sep is any nonempty sequence of commas or whitespaces
• Char is any character that does not match Sep
• Move is one of '>', '<' or '!'

The meaning of the quintuple (q, c, q', c', m) is to define the transition "when in state q and looking at character c, transition to state q', writing character c' and moving in direction m". Underscore '_' is interpreted as the blank.

Different transitions have to be separated by at least one whitespace character and the last one has to be followed by at least one whitespace character as well.

How to use

• Write (or paste) the machine instructions into the obvious text-area.
• Possibly write some input into the input box (here blanks are entered as spaces)
• Either step manually through the execution (button Step) or run automatically. The delay between steps can be adjusted using the slider.

Example machine (successor of a binary number)

1,_ 2,_,>
2,1 2,1,>
2,0 3,0,!
2,_ 4,0,<
4,1 4,0,<
4,0 4,0,<
4,_ 7,_,>
7,0 H,1,<
3,0 3,0,>
3,1 3,1,>
3,_ 5,_,<
5,0 6,1,<
5,1 5,0,<
6,1 6,1,<
6,0 6,0,<
6,_ H,_,!
           

 11111001111

Example machine (predecessor of a binary number)

1,_ 2,_,>
2,0 H,0,<
2,1 3,1,>
3,0 3,0,>
3,1 3,1,>
3,_ 4,_,<
4,0 4,1,<
4,1 5,0,<
5,1 6,1,<
5,0 6,0,<
6,0 6,0,<
6,1 6,1,<
6,_ H,_,!

5,_ 7,_,>
7,0 8,_,>
8,_ 9,_,<
9,_ H,_,<
8,1 10,1,!
10,1 11,_,<
11,_ 12,1,>
12,_ 10,_,>
10,0 13,_,<
13,_ 12,0,>
12,_ 10,_,>
10,_ 15,_,<
15,_ 14,_,<
14,0 14,0,<
14,1 14,1,<
14,_ H,_,!

 100000