My Interview with Amazon Scotland 💯

amazon.task1.js

/*
 * Task 1
 * Visible nodes in a node subtree
 */
const solution = T => visibles(T, -100000)

const visibles = (T, max) => {
  if (T === null) return 0
  
  let num = 0
  
  if (T.x >= max) {
    num = 1
    max = T.x
  }
  
  return num + visibles(T.l, max) + visibles(T.r, max)
}

amazon.task2.js

/*
 * Task 2
 * Array of pointers until -1
 */
const solution = A => {
  let index = 0, values = 0
  while (index !== -1) {
    index = A[index]
    values++
  }
  return values
}