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RLE.js
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RLE.js
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/*
* RLE (Run Length Encoding) is a simple form of data compression.
* The basic idea is to represent repeated successive characters as a single count and character.
* For example, the string "AAAABBBCCDAA" would be encoded as "4A3B2C1D2A".
*
* @author - [ddaniel27](https://github.com/ddaniel27)
*/
function Compress(str) {
let compressed = ''
let count = 1
for (let i = 0; i < str.length; i++) {
if (str[i] !== str[i + 1]) {
compressed += count + str[i]
count = 1
continue
}
count++
}
return compressed
}
function Decompress(str) {
let decompressed = ''
let match = [...str.matchAll(/(\d+)(\D)/g)] // match all groups of digits followed by a non-digit character
match.forEach((item) => {
let [count, char] = [item[1], item[2]]
decompressed += char.repeat(count)
})
return decompressed
}
export { Compress, Decompress }