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how to do a loop in JS with 2 breaks [closed]

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I want to do a loop with JS that has two breaks. For example, 1 to 9, and 15 to 29. Maybe a double loop?
Its a noob question I know, but i am a beginner.
Thank you.

You can do it using a for loop like this:
for (var a = 0; a < 30; a++) {
if (a >= 1 && a <= 9) {
console.log("do this");
}
if (a >= 15 && a <= 29) {
console.log("do that");
}
}

Javascript - Sum solution [closed]

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I am getting below line in my source file and I would like to sum those values separated by pipe ("|")
There is no limit for the values coming in the line (might be 100 values)
10|20|30|40|[no limit for values] - Separator is pipe "|"
The ouptput would be 100
Please help to write a javascript function for the above query.
Regards
Jay

You should take a look at JavaScript's built-in functions: With split you can split your string into an array, with reduce you can 'reduce' your array to a single value, in that case via summation. These two links should provide you enough information for building your code.

You could try something like below:
function sum(value){
var total = 0;
var array = value.split(",").map(Number);
for( var i = 0; i < array.length; i++) {
total += array[i];
}
alert(total);
}
var value = "10|20|30|40".replace(/\|/g, ',');
console.log(sum(value));
https://jsfiddle.net/f7uqw7cL/

How do I rearrange an array with similar items so that similar items will never neighbor each other? [closed]

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So for example if I have this array:
var input = [1,1,2,4,6,7,7,1];
I want the output to be something like:
[1,2,1,4,6,7,1,7]
The order of the new array does not matter, as long as similar items will never (or at least as seldom as possible) neighbor each other.
I can use plain JavaScript as well as underscore.js.

Try the following:
var input = [1,1,2,4,6,7,7,1];
input.sort()
var output = [];
var len = input.length;
for (var i = 0; i < Math.floor((len / 2)); i++) {
output.push(input[i]);
output.push(input[len - i - 1]);
}
if (len % 2) {
var left_over = input[Math.floor(len / 2)];
if (left_over == output[0]) {
output.push(left_over);
} else {
output.unshift(left_over);
}
}
Or see http://jsfiddle.net/d0j3Lfa3/1.
The solution sorts the numbers then alternates high and low. It deals with an odd number of elements, including corner cases such as [1,1,2] and [1,2,2] where it needs to push the middle element differently to pass. Since the input is sorted, input order doesn't affect the output.
This answer may help simplify things a bit.

My first permutation lesson - what is this code missing? [closed]

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Translated (apparently wrongly) from a C++ book.
If I can get it to work, then I can start trying to understand it.
function recPermute(soFar, rest)
{
if (rest==="")
{
console.log(soFar);
}
else
{
for(i=0; i<rest.length; i++) // <<< error was in not declaring the "i"
{
var next = soFar + rest[i];
var remaining = rest.substr(0,i) + rest.substr(i+1);
recPermute(next, remaining);
}
}
}
function listPerm(s)
{
recPermute("",s);
}
listPerm("kitcap")

You need to declare i so it's scoped to recPermute:
for(var i=0; i<rest.length; i++)
Without the var, it'll be created as a global so each call to recPermute will alter it for any other calls.

for JavaScript, use charAt(), instead of using array like acessing.
var next = soFar + rest.charAt(i);

One thing that could be an issue is you are using effectively the same i for each call to the function. You need to declare a local i or it will be declared in the global scope.
for(var i = 0; ....

how can I call an unnamed instance in javascript? [closed]

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So if I make a class, and then create new instances of that class without naming them -maybe with a loop that creates a bunch of instances- how can I call a specific (or unspecific) instance? For example, if I'm generating a bunch a squares, but I want to move a specific one somewhere, how would I do that?
Sorry if this is a total noob question, or if I miss-used some terminology, but I'm pretty new to programming.
Example code:
function example(x){
this.x = x;
}
for(var i=0; i<10; i++){
new example(1);
}
//now how would I get a specific instance of examples to have x = say, 10.

You could put each square in an array and access them that way:
function Square(i){
this.index = i;
}
Square.prototype = {
constructor: Square,
intro: function(){
console.log("I'm square number "+this.index);
}
}
var squares = [];
for(var i = 0;i < 10;i++){
squares.push(new Square(i));
}
squares.forEach(function(square){
// do something with each square
square.intro();
});
Demo: http://jsfiddle.net/louisbros/MpcrT/1/