6kyu_BasicEncryption.js

// 6 kyu - Basic Encryption
// Description:

// The most basic encryption method is to map a char to another char by a certain math rule. 
// Because every char has an ASCII value, we can manipulate this value with a simple math 
// expression. For example 'a' + 1 would give us 'b', because 'a' value is 97 and 'b' value is 98.

// You will need to write a method which does exactly that -

// get a string as text and an int as the rule of manipulation, and should return encrypted 
// text. for example:
// encrypt("a",1) = "b"

// Full ascii table is used on our question (256 chars) - so 0-255 are the valid values.
// Good luck.

let encrypt = function(str, n) {
    return str.replace(/./g, a  => {  
        let temp = a.charCodeAt(0) + n;
        return temp>255 ? String.fromCharCode(temp%256) : String.fromCharCode(temp); 
    })
}