27. Remove Element Problem Solved using JavaScript.

Here's a step-by-step explanation of the code:

1. Function Definition:

let removeElement = function (nums, val) { ... }

This line defines a function named removeElement that takes two arguments:
nums: An array of numbers.
val: The value to be removed from the array.

2. Initializing Variables:

let i = 0;

This line initializes a variable i to 0. This variable will be used as a pointer to keep track of the position where the next non-val element should be placed in the array.

3. Iterating Through the Array:

for (let j = 0; j < nums.length; j++) { ... }

This for loop iterates through each element of the nums array using a variable j as the index.

4. Checking for Elements to Keep:

if (nums[j] !== val) { ... }

Inside the loop, this if statement checks if the current element at index j is not equal to the target value val.

5. Shifting Elements and Incrementing Pointer:

nums[i] = nums[j];

If the element is not equal to val, it means we need to keep it in the array. So, this line copies the element at index j to the position at index i, effectively shifting non-val elements to the left.

i++;

This line increments i to point to the next available position for a non-val element.

6. Returning the New Length:

return i;

After the loop completes, the function returns the value of i, which represents the new length of the array after removing all occurrences of val. The original array is modified in place.

7. Calling the Function and Output:

let result = removeElement([0, 1, 2, 2, 3, 0, 4, 2], 2);

This line calls the removeElement function with the array [0, 1, 2, 2, 3, 0, 4, 2] and the value 2 to remove.
console.log(result);
This line prints the value returned by the function, which will be 5 in this case, indicating the new length of the array with the 2's removed.