LeetCode #704. Binary Search

Time Complexity: O(log n)

Space Complexity: O(1)

class Solution {
    public int search(int[] nums, int target) {
        int low = 0;
        int high = nums.length -1;

        while (low <= high) {
            int mid = low + (high -low) / 2;
            if (target == nums[mid]) 
                return mid;
            else if (target < nums[mid])
                high = mid -1;
            else
                low = mid + 1;
        }
        return -1;
    } 
}