How to Skip Specific Indexes in an Array

How to skip certain array indexes?

Use this code instead:

public static int[] sortArray(int[] array) {

    int length = array.length;

    for (int i = 0; i < length - 1; i++) {
        int k = -1; // The index of last odd element
        for (int j = 0; j < length - i; j++)
            if (array[j] % 2 != 0) {
                if (k >= 0 && array[k] > array[j]) {
                    int temp = array[k];
                    array[k] = array[j];
                    array[j] = temp;
                }
                k = j;
            }
    }

    return array;
}

How to skip specific indexes in an array?

There are a few issues with your algorithm, but it boils down to this: by doing y = L.index(1) you find the first index where a 1 appears. So by doing L[y] = 0, all you can do is update the first occurence of a 1.

There is no builin to find the nth appearance and so you will have to write it.

To be consistent with list.index, I made the following index function raise a ValueError when the item is not found.

Code

def index(lst, obj, n=1):
    count = 0
    for index, item in enumerate(lst):
        if item == obj:
            count += 1
        if count == n:
            return index
    raise ValueError('{} is not in list at least {} times'.format(obj, n))

L = [1, 2, 3, 4, 1, 2, 1, 3, 0, 4]

index = index(L, 1, n=3)

L[index] = 0

print(L)

Output

[1, 2, 3, 4, 1, 2, 0, 3, 0, 4]

Alternatively, if all you want to do is replace the nth occurence, but do not care about its actual index, you can generate a new list with a list-comprehension and an itertools.count object.

Code

from itertools import count

def replace(lst, obj, repl, n=1):
    counter = count(1)
    return [repl if x == obj and next(counter) == n else x for x in lst]


L = [1, 2, 3, 4, 1, 2, 1, 3, 0, 4]

new_list = replace(L, 1, 0, n=3)
print(new_list)

Output

[1, 2, 3, 4, 1, 2, 0, 3, 0, 4]

How to exclude an array of indexes from loop

You could use the Array.includes() method.

var list = [1,2,3,4];var skipIndexes = [1,3]; 
for (var i = 0; i< list.length; i++) { if (! skipIndexes.includes(i)) {  console.log(list[i]);  }}

sportsArr[0] = "Something else"; // set the first element to something else
for(var i = 1; i < sportsArr.length; i++){ 
   // do something
}

$result = array_slice($array,5,count($array)-5, true);

var fruits, text, year, i;fruits = ["Banana", "Orange", "Apple", "Mango"];year = ["0", "1", "2", "3"];text = "<ul>";let counter = 0; // <-- define a second counterfor (i = 0; i < fruits.length; i++) {  switch (fruits[i]) {    case 'Mango':      text += "<li>" + fruits[i] + "</li>";      text += "<li><b>" + year[counter] + "</b></li>";      counter++; // <-- that only get's incremented when a case is matched      break;    case 'Pine apple':      text += "<li>" + fruits[i] + "</li>";      text += "<li><b>" + year[counter] + "</b></li>";      counter++;      break;    case 'Grape':      text += "<li>" + fruits[i] + "</li>";      text += "<li><b>" + year[counter] + "</b></li>";      counter++;      break;    case 'Banana':      text += "<li>" + fruits[i] + "</li>";      text += "<li><b>" + year[counter] + "</b></li>";      counter++;      break;  }}text += "</ul>";document.getElementById("demo").innerHTML = text;

<p id="demo"></p>