Kata

Translations appreciated

Background information

The Hamming Code is used to correct errors, so-called bit flips, in data transmissions. Later in the description follows a detailed explanation of how it works.
In this Kata we will implement the Hamming Code with bit length 3; this has some advantages and disadvantages:

• [ + ] It's simple to implement
• [ + ] Compared to other versions of hamming code, we can correct more mistakes
• [ - ] The size of the input triples

Task 1: Encode function

Implement the encode function, using the following steps:

• convert every letter of the text to its ASCII value; (ASCII value of space is 32)
• convert ASCII values to 8-bit binary;
• triple every bit;
• concatenate the result;

For example:

input: "hey"
--> 104, 101, 121                  // ASCII values
--> 01101000, 01100101, 01111001   // binary
--> 000111111000111000000000 000111111000000111000111 000111111111111000000111  // tripled
--> "000111111000111000000000000111111000000111000111000111111111111000000111"  // concatenated

Task 2: Decode function:

Check if any errors happened and correct them. Errors will be only bit flips, and not a loss of bits:

• 111 --> 101 : this can and will happen
• 111 --> 11 : this cannot happen

Note: the length of the input string is also always divisible by 24 so that you can convert it to an ASCII value.

Steps:

• Split the input into groups of three characters;
• Check if an error occurred: replace each group with the character that occurs most often, e.g. 010 --> 0, 110 --> 1, etc;
• Take each group of 8 characters and convert that binary number;
• Convert the binary values to decimal (ASCII);
• Convert the ASCII values to characters and concatenate the result

For example:

input: "100111111000111001000010000111111000000111001111000111110110111000010111"
--> 100, 111, 111, 000, 111, 001, ...  // triples
-->  0,   1,   1,   0,   1,   0,  ...  // corrected bits
--> 01101000, 01100101, 01111001       // bytes
--> 104, 101, 121                      // ASCII values
--> "hey"

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