BinarySearch.js

var search = function(nums, target) {
    let ind = (x) => x === target;
    return nums.findIndex(ind)
 };

 /*

 Given a sorted (in ascending order) integer array nums of n elements and a target value, 
 write a function to search target in nums. If target exists, then return its index, otherwise return -1.


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
 

Note:

You may assume that all elements in nums are unique.
n will be in the range [1, 10000].
The value of each element in nums will be in the range [-9999, 9999].

 */