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duccanhole
duccanhole

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code every day with me

--DAY 7--
Hi, I am going to make #100DaysOfCode Challenge. Everyday I will try solve 1 problem from leetcode or hackerrank. Hope you can go with me until end.
Now let's solve problem today:
-Problem: Remove Element
-Detail: https://leetcode.com/problems/remove-element/
-My solution (javascript):

var removeElement = function(nums, val) {
    let i=0;
    for(let j=0;j<nums.length;j++)
        if(nums[j]!=val){
            nums[i]=nums[j];
            i++;
        }
    return i;
};
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-->If you have better solution or any question, please comment below. I will appreciate.

Top comments (2)

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grendel profile image
grendel • Edited

I think you should change return i to return nums.splice(--i).length since if you run this function over the same array multiple times, it can eventually start putting formerly-removed elements back into the array (or work on an array whose "real length" should be 0 long ago) since subsequent iterations will traverse all the way to original index N, when the length should be N-i each time. In a language that can't resize an array, like C for example, this would be accomplished by placing a null byte at index i to stop traversal at the new length on subsequent runs.

Edit: it just occurred to me that in C, null-termination is a thing for character arrays (strings) and other such potentially variable-length arrays, and not for every array, like ints. It only would matter if code that iterates over the array will check for and stop on a null byte. Otherwise, returning the number of erased elements should be enough, since it should be calling code's responsibility to subtract that from wherever the array's length is recorded.

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coderduck profile image
duccanhole

I only code by js, so i dont know that. Thank you!