https://github.com/stardustdl/turing-machine-emulator
An emulator for multi-tape deterministic turing machine.
https://github.com/stardustdl/turing-machine-emulator
emulator nju nju-cs turing-machine
Last synced: about 2 months ago
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An emulator for multi-tape deterministic turing machine.
- Host: GitHub
- URL: https://github.com/stardustdl/turing-machine-emulator
- Owner: StardustDL
- License: mpl-2.0
- Created: 2021-12-07T06:39:12.000Z (over 3 years ago)
- Default Branch: main
- Last Pushed: 2021-12-30T02:40:26.000Z (over 3 years ago)
- Last Synced: 2025-02-07T13:51:03.722Z (4 months ago)
- Topics: emulator, nju, nju-cs, turing-machine
- Language: Python
- Homepage:
- Size: 30.3 KB
- Stars: 3
- Watchers: 1
- Forks: 1
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
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README
 
An emulator for multi-tape deterministic turing machine.
## Turing Machine Description Language
### Metadata
Each line of metadata is in form `# = ` where `` is the metadata id, and `` is the metadata value.
```
; the finite set of states
#Q = {0,cp,cmp,mh,accept,halt_accept,reject,halt_reject}
; the finite set of input symbols
#S = {0,1}
; the complete set of tape symbols
#G = {0,1,_,T,r,u,e,F,a,l,s}
; the start state
#q0 = 0
; the blank symbol
#B = _
; the set of final states
#F = {halt_accept}
; the number of tapes
#N = 2
```
The metadata can be inferred (replaced) by transfer edges using auto mode in parser.
- Use `0` as start state if not defined.
- Use `_` as blank symbol if not defined.
- Any state starting with 'halt', eg. halt, halt-accept, will be a final state.
### Transfer Edges
- Each line of transfer edge should contain one tuple of the form ` `.
- You can use any number or word for `` and ``, eg. 10, a, state1. State labels are case-sensitive.
- You can use almost any character for `` and ``, or `_` to represent blank (space). Symbols are case-sensitive.
- You can't use `;`, `*`, `_` or whitespace as symbols.
should be `l`, `r` or `*`, denoting 'move left', 'move right' or 'do not move', respectively.
- Anything after a `;` is a comment and is ignored.
- `*` can be used as a wildcard in `` or `` to match any character or state.
- `*` can be used in `` or `` to mean 'no change'.
- `!` can be used at the end of a line to set a breakpoint, eg. `1 a b r 2 !`.
## Parser
The parser will parse the text in the description language, and check the semantic:
- All states are declared in Q
- All symbols are declared in G
- S is a subset of Q
- q0 is in Q
- B is in G
- F is a subset of Q
- N is a positive integer
## Emulator
It emulates a multi-tape deterministic turing machine.
## Build
```sh
$ cd ./turing-project
$ chmod +x ./build.sh
$ bash -c ./build.sh
```
## Run
```sh
./turing
```
Possible flags:
- `-v/--verbose` Details about error in parser and execution states in emulator.
- `-a/--auto` Use the metadata inferred from transfer edges when parsing.
- `-d/--debug` Pause the emulator when a breakpoint hits.
```sh
$ ./turing ./samples/gcd.tm 11110111111
11
$ ./turing ./samples/gcd.tm 11110111111 -v
Input: 11110111111
==================== RUN ====================
Step : 0
Index0 : 0 1 2 3 4 5 6 7 8 9 10
Tape0 : 1 1 1 1 0 1 1 1 1 1 1
Head0 : ^
Index1 : 0
Tape1 : _
Head1 : ^
Index2 : 0
Tape2 : _
Head2 : ^
State : 0
---------------------------------------------
Step : 1
Index0 : 0 1 2 3 4 5 6 7 8 9 10
Tape0 : 1 1 1 1 0 1 1 1 1 1 1
Head0 : ^
Index1 : 0
Tape1 : _
Head1 : ^
Index2 : 0
Tape2 : _
Head2 : ^
State : pre1
---------------------------------------------
Step : 2
Index0 : 0 1 2 3 4 5 6 7 8 9 10
Tape0 : 1 1 1 1 0 1 1 1 1 1 1
Head0 : ^
Index1 : 0 1
Tape1 : 1 _
Head1 : ^
Index2 : 0
Tape2 : _
Head2 : ^
State : pre1
---------------------------------------------
...
---------------------------------------------
Step : 150
Index0 : 0 1 2
Tape0 : 1 1 _
Head0 : ^
Index1 : 0 1 2 3
Tape1 : 1 1 1 1
Head1 : ^
Index2 : 0 1 2 3 4 5 6
Tape2 : 1 1 1 1 1 1 _
Head2 : ^
State : test2
---------------------------------------------
Step : 151
Index0 : 0 1
Tape0 : 1 1
Head0 : ^
Index1 : 0 1 2 3
Tape1 : 1 1 1 1
Head1 : ^
Index2 : 0 1 2 3 4 5
Tape2 : 1 1 1 1 1 1
Head2 : ^
State : final
---------------------------------------------
Result: 11
==================== END ====================
```
## Samples
`/samples` contains some sample turing machines.
> Some of the samples are from [jsturing](https://github.com/awmorp/jsturing). These samples need to use `auto` mode to parse.