1
exercism fetch javascript ocr-numbers

Ocr Numbers

Given a 3 x 4 grid of pipes, underscores, and spaces, determine which number is represented, or whether it is garbled.

Step One

To begin with, convert a simple binary font to a string containing 0 or 1.

The binary font uses pipes and underscores, four rows high and three columns wide.

1
2
3
4
     _   #
    | |  # zero.
    |_|  #
         # the fourth row is always blank

Is converted to "0"

1
2
3
4
         #
      |  # one.
      |  #
         # (blank fourth row)

Is converted to "1"

If the input is the correct size, but not recognizable, your program should return '?'

If the input is the incorrect size, your program should return an error.

Step Two

Update your program to recognize multi-character binary strings, replacing garbled numbers with ?

Step Three

Update your program to recognize all numbers 0 through 9, both individually and as part of a larger string.

1
2
3
4
 _ 
 _|
|_ 

Is converted to "2"

1
2
3
4
      _  _     _  _  _  _  _  _  #
    | _| _||_||_ |_   ||_||_|| | # decimal numbers.
    ||_  _|  | _||_|  ||_| _||_| #
                                 # fourth line is always blank

Is converted to "1234567890"

Step Four

Update your program to handle multiple numbers, one per line. When converting several lines, join the lines with commas.

1
2
3
4
5
6
7
8
9
10
11
12
    _  _ 
  | _| _|
  ||_  _|

    _  _ 
|_||_ |_ 
  | _||_|

 _  _  _ 
  ||_||_|
  ||_| _|

Is converted to "123,456,789"

Setup

Go through the setup instructions for JavaScript to install the necessary dependencies:

http://exercism.io/languages/javascript/installation

Making the Test Suite Pass

Execute the tests with:

1
jasmine <exercise-name>.spec.js

Replace <exercise-name> with the name of the current exercise. E.g., to test the Hello World exercise:

1
jasmine hello-world.spec.js

In many test suites all but the first test have been skipped.

Once you get a test passing, you can unskip the next one by changing xit to it.

Source

Inspired by the Bank OCR kata http://codingdojo.org/cgi-bin/wiki.pl?KataBankOCR

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.