CoDEVIANT #10 (4/2/19)

I was going to make an entry yesterday, but somehow I felt that given the holiday I needed to save my foolishness for today…I’m actually in rehearsal and need to run on stage in a second *quite literally*. Come see Don Giovanni presented by Opera Bend if you happen to be in Bend, Oregon. April 5, 6, and 7th!

Problem 1: Encrypt this!

Instructions:

Description:

Encrypt this!

You want to create secret messages which can be deciphered by the Decipher this! kata. Here are the conditions:

1. Your message is a string containing space separated words.
2. You need to encrypt each word in the message using the following rules:

• The first letter needs to be converted to its ASCII code.
• The second letter needs to be switched with the last letter

1. Keepin’ it simple: There are no special characters in input.

Examples:

encryptThis("Hello") === "72olle"
encryptThis("good") === "103doo"
encryptThis("hello world") === "104olle 119drlo"

(https://www.codewars.com/kata/5848565e273af816fb000449/train/javascript)

How Adrian Solved It:

var encryptThis = function(text) {
let answer = [];
   function go(array){
       let secondLetterValue = array[1];
      array[0] = array[0].charCodeAt(0);
      array[1] = array[array.length-1];
      array[array.length-1] = secondLetterValue;
      answer.push(array.join(‘’));
   }
text = text.split(‘ ‘);
    text.forEach(function(word){
      word = word.split(‘’);
      go(word);
    });
return answer.join(‘ ‘);
}

• I make a variable that is an empty array called answer
• I make text equal itself when it has the .split( ) method called on it with a space separating the elements in the new array to be made.
• On the array that is now text, I call the .forEach( ) method on it with word as a placeholder argument representing each element in the text array when it goes through the for loop implied by the method .forEach( ).
• Inside the code block, I make word equal itself with .split(‘’) being used on it so that it creates an array.
• Then we call the function go with the word-array we made as an argument.
• Earlier I made a function inside our function called go.
• In our new function we make a new variable called secondLetterValue = array[1]. The second element in the array argument that we pass in.

let secondLetterValue = array[1];

• I make the first character in the array argument equal itself converted into an ASCII code-character

array[0] = array[0].charCodeAt(0);

• I make the second character in the array argument equal the last character in the array argument

array[1] = array[array.length-1];

• I make the last character int he array argument equal secondLetterValue, the original value of what had been the 2nd element in the array at the start of this sub function.
• Then I push into the array answer our array argument made into a string with .join(‘’), now that all the appropriate alterations have been done.

“Best Practices Answer”

const encryptThis = text => text
.split(‘ ‘)
.map(word => word .replace(/(^\w)(\w)(\w*)(\w$)/, `$1$4$3$2`) .replace(/^\w/, word.charCodeAt(0))) .join(‘ ‘);

So these guys are smart, smart people. They solved it in these steps:

• Like me, they used .split( ) on the text argument. We separate elements based on whether there is a space between them as normal words do.
• After this, they chain the .map( ) array function onto what is now an array and pass in the argument word to represent each element in the text array.
• for each word element in the text array, we use the string method .replace( ),
• as the first argument, we seek the
• first character => (^\w)
• second character => (\w)
• third character => (\w*)
• fourth character => (\w$)
• as the second argument, we pass in
• $1 — the first character is going to be (^\w)
• $4 — the fourth character will be in the place of where the second one should be (\w$)
• $3 — the third (\w*)
• $2 — the second character (\w)
• .replace( ) is called and we replace the first character [represetned by this RegEx expression] : /^\w/ with whatever the ASCII key for the character being referenced by the RegEx expression via the following string method word.charCodeAt(0).
• You use 0 with the .charCodeAt( ) method to get an ASCII character returned to you.
• Then we join it all together with .split( ).

That’s all folks, I gotta run!