Given a sorted array and a target value, return the index if the target is found. If not, return the index where it would be if it were inserted in order.

search_insert.go

func searchInsert(nums []int, target int) int {
    start, end := 0, len(nums)
    if len(nums) == 0 || target < nums[start] {
        return 0
    } else if target > nums[end-1] {
        return len(nums)
    }
    return getIndex(start, end, target, nums)
}

func getIndex(start, end, target int, nums []int) int { 
    pivot := (start+end) / 2 
    if start >= end || pivot > end{
        return end
    } else if nums[pivot] == target {
        return pivot
    } else if nums[pivot] > target {
        return  getIndex(start, pivot, target, nums)
    } else {
        return  getIndex(pivot+1, end , target, nums)
    }    
}