Jump Search

Write a function `jump_search(arr, target)` that returns the index of `target` in the sorted list `arr` using the jump search algorithm. If `target` is not present, return `-1`. **Algorithm specification:** 1. Let `n = len(arr)`. Choose the block size `step = int(n ** 0.5)` (integer square root). If `n == 0`, return `-1`. 2. Start at index `prev = 0` and `curr = step`. While `curr < n` and `arr[curr] < target`, set `prev = curr`, `curr += step`. Stop when `curr >= n` or `arr[curr] >= target`. 3. Perform a linear search from `prev` to `min(curr, n-1)` inclusive. If `arr[i] == target` at some index `i`, return `i`. 4. If not found, return `-1`. Assume `arr` is sorted in non-decreasing order. The function must work for any list of comparable values (integers, floats, strings, etc).

>>> jump_search([1, 3, 5, 7, 9], 5)
2
>>> jump_search([1, 3, 5, 7, 9], 6)
-1
>>> jump_search([], 10)
-1
>>> jump_search([10], 10)
0