leetcode_27_remove_element.go

leetcode_27_remove_element.go

// https://leetcode.com/problems/remove-element/description/

func removeElement(nums []int, val int) int {
    if len(nums) == 0 {
        return 0
    }
    writeptr := len(nums)-1
    readptr := 0

    // replace val with number from the back
    // on each replace move the writeptr one to the front
    for ; readptr<writeptr;readptr++ {
        if nums[readptr]==val {
            nums[readptr] = nums[writeptr]
            writeptr--
            // have to retry again, so reset readptr, 
            // as it is incremented each iteration
            readptr--
        }
    }

    // if iteration stopped pointing on the searched val
    if readptr==writeptr && nums[readptr]==val {
        return readptr 
    }
    return readptr+1
}