zenefits.js

//1
// This is the text editor interface. 
// Anything you type or change here will be seen by the other person in real time.
// An "expression" is either a number, or a list (AKA vector/array) with the first element one of '+', '-', '*', '/' , 
// and then other expressions.
// Write a function "evaluate" that gets an expression and returns its value
console.log(calculate(['+', 1, 2])) // --> 3
console.log(calculate(['*', 3, ['+', 1, 10]]))// --> 33
console.log(calculate(['+', 1000, 1200]))//  --> 2200
console.log(calculate(['/', 6, ['+', 1, ['*', 1, 1]]]))//  --> 3
console.log(calculate(['+', 1, 2, 3]))//  --> 6
console.log(calculate(['+', ['*', 1, 2], 3]))//  --> 5
console.log(calculate(['-', ['*', 5, 5], ['*', 2, 2, 2]]))//  --> 17
// Assume - / -- only take two operands8 {3 y( A# [$ ~4 p
// + * take any number of operands

function calculate(arr){
  if(arr.length < 3) return null
  var o = arr[0]
  var first
  var result
  if(typeof arr[1] === 'number') first = arr[1]
  else{
    first = calculate(arr[1])
  }
  for(var i = 2; i < arr.length; i++){
    var second
    if(typeof arr[i] === 'number') second = arr[i]
    else{
      second = calculate(arr[i])
    }
    result = eval(first + o + second) 
    first = result
  }
  
  return result
}

//2
var input = [
    ['A', 'B'],
    ['C', 'B'],
    ['D', 'A'],
    ['B', 'E']
]

main(input, 'B')

// print:
// '-A', 
// '--D', 
// '-C'

function Node(name){
  this.name = name
  this.children = []
}

function main(arr, manager){
  var hash = generateTree(arr)
  var root = hash[manager]
  root.children.forEach(function(child){
    dfs(child, '')
  })
}

function dfs(root, str){
  if(root === null) return;
  str += '-'
  console.log(str + root.name)
  root.children.forEach(function(child){
    dfs(child, str)
  })
}
  
function generateTree(arr){
  var hash = {}

  arr.forEach(function(path){
    var current = null
    for(var i = path.length - 1; i >= 0; i--){
      var key = path[i];
      if(!hash.hasOwnProperty(key)){
        var node = new Node(key)
        hash[key] = node
      }else{
        var node = hash[key]
      }
      if(current){
        current.children.push(node);
      }
      current = node
    }
  })
  
  return hash
}