Problem Statement:
Given an array of integers nums which is sorted in ascending order, and an integer target, write a function to search target in nums. If target exists, then return its index.
Otherwise, return -1.
You must write an algorithm with O(log n) runtime complexity.

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

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

Constraints:
1 <= nums.length <= 104
-104 < nums[i], target < 104
All the integers in nums are unique.
nums is sorted in ascending order.

Solution:

class Solution {
    public int search(int[] nums, int t) {
        return bsearch(nums,t,0,nums.length-1);
    }
    public int bsearch(int []nums, int t, int l, int high)
    {
        if(high<l)
            return -1;
        int mid = l+(high-l)/2;
        if(nums[mid]==t)
            return mid;
        if(nums[mid]>t)
            return bsearch(nums,t,l,mid-1);
        return bsearch(nums,t,mid+1,high);
    }
}

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