Interview Question

Software Engineer Intern Interview(Student Candidate) Penn State University, PA

Main question was verifying whether a binary tree was a

  BST, given the function header that looked like public boolean isBST(root). He stated no other functions could be created and that child nodes did not have links to their parents.
Answer

Interview Answer

2 Answers

0

He was looking for me to use a helper function to pass the parent's value in.

boolean isBST(Node root) {
   return isBSTHelper(root.left, root.value, isLeft) && isBSTHelper(root.right, root.value, isRight);
}

something similar to this. Since he told me I could not use extra functions I could not come up with an answer which is why I am bitter / negative about this interview.

Interview Candidate on Apr 2, 2014
0

Basically, what you would have in isBST is the stop condition (i.e. if left < current-node < right), then recursively whether isBST(left) && isBST(right) is true.

Khoa on Apr 5, 2014

Add Answers or Comments

To comment on this question, Sign In with Facebook or Sign Up