Misiu Misiu - 2 months ago 6
Javascript Question

remove trailing elements from array that are equal to zero - better way

I have very long array containing numbers. I need to remove trailing zeros from that array.

if my array will look like this:

var arr = [1,2,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0];


I want to remove everything except
[1, 2, 0, 1, 0, 1]
.

I have created function that is doing what is expected, but I'm wondering if there is a build in function I could use.

var arr = [1,2,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0];
for(i=arr.length-1;i>=0;i--)
{
if(arr[i]==0)
{
arr.pop();
} else {
break;
}
}
console.log(arr);


Can this be done better/faster?

Answer

Assuming:

var arr = [1,2,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0];

You can use this shorter code:

while(arr[arr.length-1] === 0){ // While the last element is a 0,
    arr.pop();                  // Remove that last element
}

Result:

arr == [1,2,0,1,0,1]