# Leetcode 702: Search in a Sorted Array of Unknown Size

Given an integer array sorted in ascending order, write a
function to search target in nums. If target exists, then
return its index, otherwise return -1. However, the array
size is unknown to you. You may only access the array using
an ArrayReader interface, where ArrayReader.get(k) returns
the element of the array at index `k` (0-indexed).

You may assume all integers in the array are less than
`10000`, and if you access the array out of bounds,
`ArrayReader.get` will return `2147483647`.

Example 1:

```
Input: array = [-1,0,3,5,9,12], target = 9
Output: 4
Explanation: 9 exists in nums and its index is 4
```

Example 2:

```
Input: array = [-1,0,3,5,9,12], target = 2
Output: -1
Explanation: 2 does not exist in nums so return -1
```

Note:

1. You may assume that all elements in the array are unique.
2. The value of each element in the array will be in the
   range [-9999, 9999].