Turing

Tape

Program

Program Trace

Challenges and Examples

Many of these were pulled from https://codingbat.com

Monkey Trouble

We have two monkeys, a and b. Position 0 of the tape will be "1" if monkey a is smiling, and "0" if not. Similarly, Position 1 of the tape will be "1" if monkey b is smiling, and "0" if not. We are in trouble if they are both smiling or if neither of them is smiling. If we are in trouble, write "T" to position 0, otherwise write "F".

Test Cases

00 - T
01 - F
10 - F
11 - T

Example Solution

start:
gotoif 0 foundleft0
gotoif 1 foundleft1
foundleft0:
right
gotoif 0 same
gotoif 1 different
foundleft1:
right
gotoif 1 same
gotoif 0 different
same:
left
write T
break
different:
left
write F

Language Specification

Commands

[Label]: - Defines a named label used for jumping
Goto [label] - Jump to the specified label
Gotoif [condition] [label] - Jump to the specified label if the condition matches the contents of the current cell. If the condition is %, the jump will occur if the current cell is the leftmost cell
Break - End program execution
Write [value] - Write the specified value to the current cell
Increment/Incr - Increment the value of the current cell
Decrement/Decr - Decrement the value of the current cell
Left - Move the pointer left
Right - Move the pointer right

Tips

Commands are not case-sensitive, but labels are
If a `9` is incremented, it will become an `a`. A `z` becomes a `0`. Decrementing works in reverse.
New cells will spawn automatically at the right, therefore the tape is infinite
# or / can be used to denote a comment line
All computations can be performed in this interpreter with enough time