[JS] Build BST from sorted array

buildBST.js

function buildBST(sortedArray) {
  if(!sortedArray.length) return null;
  if(sortedArray.length === 1) return new Node(sortedArray[0]);
  
  const rootIndex = Math.floor(sortedArray.length / 2);
  const root = new Node(sortedArray[rootIndex]);
  root.left = buildBST(sortedArray.slice(0, rootIndex));
  root.right = buildBST(sortedArray.slice(rootIndex + 1));
    
  return root;
}

// -------------------------------------- Test ------------------------------//
class Node {
  constructor(data) {
    this.data = data;
    this.right = null;
    this.left = null;
  }
}

const arr = [2,5,6,6,7,8,9,10];
console.log(buildBST(arr));
// Node {
//   data: 7,
//   right: Node {
//     data: 9,
//     right: Node { data: 10, right: null, left: null },
//     left: Node { data: 8, right: null, left: null }
//   },
//   left: Node {
//     data: 6,
//     right: Node { data: 6, right: null, left: null },
//     left: Node { data: 5, right: null, left: [Node] }
//   }
// }