So a friend of mine asked if I could do a function that compresses strings. That function compresses a string if one character repeats itself more than four times, like: "abbbbbbcccdddd" will turn into "a#6bccc#4d". I'm noob and I wanna improve. Thank u for who is answering me :).
let text = '92HSSSS9U27888YSGGGGGG28SLKHFKLSPPPPSKWWW'
function compressText(text){
return searchIqualLetters(text)
}
function searchIqualLetters(originalText){
let modifyedText = ''
for(let i = 0; i < originalText.length - 1; i++){
for(let j = i + 1; j < originalText.length; j++){
modifyedText = repeatFourTimes(i, j, originalText)
if(modifyedText !== undefined && modifyedText !== ''){
originalText = modifyedText
}
}
}
return originalText
}
function checkTextModifyed(){
}
function repeatFourTimes(i, j, text){
if(text[i] == text[j] && text[i] == text[j + 1] && text[i] == text[j + 2]){
return getLastIqualLetter(i, j, text)
}
}
function getLastIqualLetter(i, j, text){
let lastIqualLetterPosition = 0
for(let k = 0; text[i] == text[j + k]; k++){
lastIqualLetterPosition = j + k
}
return makeNewText(i, lastIqualLetterPosition, text)
}
function makeNewText(i, lastLetter, text){
let cutedPart = text.slice(i, lastLetter + 1)
let startPart = text.slice(0, i)
let centerPart = '#' + cutedPart.length + cutedPart[0]
let endPart = text.slice(lastLetter + 1, text.length)
return startPart + centerPart + endPart
}
console.log(compressText(text)) // Result: 92H#4S9U27888YS#6G28SLKHFKLS#4PSKWWWHere's my take on the problem:
function condense(text) {
let count = 0;
let out = "";
text.split("").forEach((el, i, arr) => { // el = current letter, i = index of letter, arr = the input text as an array
if (arr[i + 1] != el) { // if the next letter is not the same as the current one
if (count < 3) {
out += el.repeat(count + 1) // if the sequence is less than 3 letters, then just do it normally
} else {
out += "#" + (count + 1) + el; // else, condense it
}
count = 0; // reset sequence length
} else {
count += 1; // increase count of repeated letter sequence length
}
})
return out;
}
console.log(condense("aaabbbbcdddddee")); // Output: "aaab#4cd#5ee"
console.log(condense('92HSSSS9U27888YSGGGGGG28SLKHFKLSPPPPSKWWW'));
console.log("92H#4S9U27888YS#6G28SLKHFKLS#4PSKWWW (reference)");Here is my take on it:
const text = '92HSSSS9U27888YSGGGGGG28SLKHFKLSPPPPSKWWW';
function compr(txt){
let cnt=1,arr=[];
txt.split("").reduce((p,c,i)=>{
if(c==p) cnt++;
if(c!=p || i==txt.length-1) {
arr.push(cnt>3?`#${cnt}${p}`:p.repeat(cnt));
cnt=1;
}
return c;
});
return arr.join("");
}
console.log(compr(text));
console.log("92H#4S9U27888YS#6G28SLKHFKLS#4PSKWWW (reference)");The core of the action happens in the .reduce() loop. Here I compare the current character c with the previous one(p). If it is the same I simply increase the counter cnt otherwise - or in case I have reached the end of the string (i==txt.length-1) - I add the latest group of character in its suitable form to arr and reset cnt to 1. The arr array is eventually .join()ed and returned as the resulting string.