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JavaScript: How to create a function that receives an array of numbers and returns an array containing only the positive numbers? [closed]

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What is Wrong with this Code? I should create a function that receives an array of numbers and returns an array containing only the positive numbers. How can it be modified? Especially Modified. Not another code!
all = prompt("Give me an array of numbers seperated by ','");
var splitted = all.split`,`.map(x=>+x);
function returner(splitted){
var positive = [];
for(var i = 0; i < splitted.length; i++);{
var el = splitted[i];
if (el >= 0){
positive.push(el);
}
}
return positive;
}
var positive = returner(splitted);
print(positive);

First I noticed that you are using print to check your output - that should be console.log().
But your real mistake is the semicolon after the for bracket in line 7.
Here is a working code-snippet:
let all = prompt("Give me an array of numbers seperated by ','");
let splitted = all.split`,`.map(x => +x);
function returner(splitted) {
let positive = [];
for (let i = 0; i < splitted.length; i++) {
const el = splitted[i];
if (el >= 0) {
positive.push(el);
}
}
return positive;
}
var positive = returner(splitted);
console.log(positive);

Just remove the semicolon after the for statement as:
all = prompt("Give me an array of numbers seperated by ','");
var splitted = all.split`,`.map(x=>+x);
function returner(splitted){
var positive = [];
for(var i = 0; i < splitted.length; i++){
var el = splitted[i];
if (el >= 0){
positive.push(el);
}
}
return positive;
}
var positive = returner(splitted);
console.log(positive);
practically with that semicolon you were doing "nothing" n times and then executing the block on it's own which didn't help filling your array since the i variable is already passed the last index of the array and so splitted[i] results to undefined which is not >=0 thus nothing gets pushed to the positive array.
(also I'd imagine you want a console.log at the end instead of print? )

Why don't you use filter?
var array = [3, -1, 0, 7, -71, 9, 10, -19];
const getpositiveNumbers = (array) => array.filter(value => value > 0);
var positives = getpositiveNumbers(array);
console.log(positives);
Anyway, as #trincot noticed, your code is wrong.

Get palindrome length from string [closed]

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I have one string as "testaabbaccc" in this string we contain palindrome as "abba" and it's length is 4 but how can we identify this with a JavaScript code.
var string ="testaabbaccc"
Need Output as abba is palindrome and length is 4

You can use this article and modify it to your needs.
Working demo
function isPalindrome(s) {
var rev = s.split("").reverse().join("");
return s == rev;
}
function longestPalind(s) {
var maxp_length = 0,
maxp = '';
for (var i = 0; i < s.length; i++) {
var subs = s.substr(i, s.length);
for (var j = subs.length; j >= 0; j--) {
var sub_subs = subs.substr(0, j);
if (sub_subs.length <= 1)
continue;
if (isPalindrome(sub_subs)) {
if (sub_subs.length > maxp_length) {
maxp_length = sub_subs.length;
maxp = sub_subs;
}
}
}
}
return maxp;
}
console.log(longestPalind("testaabbaccc"));
console.log(longestPalind("testaabbaccc").length);
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

Javascript: Find the second longest substring from the given string Ex: I/p: Aabbbccgggg o/p: bbb [closed]

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Javascript:Find the second longest substring from given string(input and output example added in heading)

Try this
Get sequences using RegExp
Sort them based on string length
Select second Item
function getSecondSubstring(str){
let regex = new RegExp(str.toLowerCase().split("").filter((x,i,a)=>a.indexOf(x)===i).join("+|")+"+", "ig")
let substrgroups = str.match(regex);
substrgroups.sort((a,b)=> b.length-a.length);
return substrgroups[1]
}
console.log(getSecondSubstring("ööööööðððób"));
console.log(getSecondSubstring("Aabbbccgggg"));

If you don't mind using regular expressions:
function yourFunctionName(input){
let grp = input.split(/(?<=(.))(?!\1|$)/ig);
grp.sort((a,b)=> b.length-a.length);
if(grp.length <= 0){
return null;
}
else if (grp.length == 1){
return grp[0];
}
else{
grp.sort(function(a, b){
return b.length - a.length;
});
return grp[1];
}
}
console.log(yourFunctionName("ööööööðððób"));
Or another way which does not use regular expressions...
function yourFunctionName(input){
input = input.toLowerCase();
let counter = [];
let prevChar;
let countIndex = 0;
for (let index = 0, length = input.length; index < length; index++) {
const element = input[index];
if(prevChar){
if(prevChar != element){
countIndex++;
counter[countIndex] = "";
}
}
else{
counter[countIndex] = "";
}
counter[countIndex] += element;
prevChar = element;
}
if(counter.length <= 0){
return null;
}
else if (counter.length == 1){
return counter[0];
}
else{
counter.sort(function(a, b){
return b.length - a.length;
});
return counter[1];
}
}
console.log(yourFunctionName("aaaaabbbbccdd"));

Need to add one by one value to comma separated List from array [closed]

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I need to add one bye one value to comma separated list
my code
var Plist, Llist;
for (var i = 0; i < results.length; i++) {
var id = results[i].id;
if (id.startsWith("P")) {
Plist = // Add comma separated value
} else if (id.startsWith("L")) {
Llist = // add comma repeated value
}
}
please suggest better solution...

var Plist = "", Llist = "";
for (var i = 0; i < results.length; i++) {
var id = results[i].id;
if (id.startsWith("P")) {
Plist += id + ",";
} else if (id.startsWith("L")) {
Llist += id + ",";
}
}
if (Plist.indexOf(',') !== -1) {
Plist = Plist.substring(0, Plist.length - 1);
}
if (Llist.indexOf(',') !== -1) {
Llist = Llist.substring(0, Llist.length - 1);
}

convert string to array of numbers in javascript [closed]

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Closed 8 years ago.
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How to convert below String into arrays in javascript
var data = "[
[[1400586475733,-1],
[1400586535736,-1],
[1400586595739,-1],
[1400586655742,-1],
[1400586715745,-1]],
[[1400586475733,0],
[1400586535736,0],
[1400586595739,0],
[1400586655742,0],
[1400586715745,0]]
]";
expected output is
data[0] = [[1400586475733,-1],[1400586535736,-1],[1400586595739,-1],[1400586655742,-1],[1400586715745,-1]]; ==> of type object Array
data[0][0] = 1400586475733 ==> of type number
data[0][1] = -1 ==> of type number

I haven't tried it out thoroughly, but it should work:
var string = "[[[1400586475733,-1],[1400586535736,-1],[1400586595739,-1],[1400586655742,-1],[1400586715745,-1]],[[1400586475733,0],[1400586535736,0],[1400586595739,0],[1400586655742,0],[1400586715745,0]]]";
var dataFromString = string.split(",");
var finalArray = [];
var arrayStartRegEx = new RegExp(/^\[/);
var arrayEndRegEx = new RegExp(/\]$/);
var currentArray = finalArray;
var arrayHistory = [];
for(var i = 0; i < dataFromString.length; i++) {
var currentString = dataFromString[i];
var closingArray = false;
while(arrayStartRegEx.test(currentString) === true) {
// Save previous array
// createArray
// add to big array
// currentArray = createdArray
// remove bracket
var arr = []
arrayHistory.push(currentArray);
currentArray.push(arr);
currentArray = arr;
currentString = currentString.slice(1,currentString.length - 1);
}
while(arrayEndRegEx.test(currentString) === true){
// remove bracket
// add element to array
// close currentArray
// currentArray = big array
currentString = currentString.slice(0,-1);
if(!closingArray) {
var string = currentString.replace(/\]/g, '');
// Use parseFloat if you know it's going to be a float
currentArray.push(parseInt(string));
closingArray = true;
}
currentArray = arrayHistory.pop();
}
if(arrayStartRegEx.test(currentString) === false && arrayEndRegEx.test(currentString) === false) {
// add element to array
currentArray.push(parseInt(currentString))
}
}
console.log(finalArray);