Write a function to search target in nums

BinarySearchEasy1.js

// Binary Search Easy 1
// 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.

const nums = [-1, 0, 3, 5, 9, 12];

function getIndex(numList, target) {
  
  let left = 0;
  let right = numList.length - 1
  
  while (left <= right) {
    const pivotal = Math.floor((right + left) / 2)
    
    if(target === numList[pivotal]) {
      return pivotal
    }
    
    if(target < numList[pivotal]) {
      right = pivotal -1
    } else {
      left = pivotal + 1
    }
  }
  
  return -1
}

console.log(getIndex(nums, 9))