Class Solution


  • public class Solution
    extends Object
    1361 - Validate Binary Tree Nodes.

    Medium

    You have n binary tree nodes numbered from 0 to n - 1 where node i has two children leftChild[i] and rightChild[i], return true if and only if all the given nodes form exactly one valid binary tree.

    If node i has no left child then leftChild[i] will equal -1, similarly for the right child.

    Note that the nodes have no values and that we only use the node numbers in this problem.

    Example 1:

    Input: n = 4, leftChild = [1,-1,3,-1], rightChild = [2,-1,-1,-1]

    Output: true

    Example 2:

    Input: n = 4, leftChild = [1,-1,3,-1], rightChild = [2,3,-1,-1]

    Output: false

    Example 3:

    Input: n = 2, leftChild = [1,0], rightChild = [-1,-1]

    Output: false

    Constraints:

    • n == leftChild.length == rightChild.length
    • 1 <= n <= 104
    • -1 <= leftChild[i], rightChild[i] <= n - 1
    • Constructor Detail

      • Solution

        public Solution()
    • Method Detail

      • validateBinaryTreeNodes

        public boolean validateBinaryTreeNodes​(int n,
                                               int[] leftChild,
                                               int[] rightChild)