标签：art class work main nod function eth alt let
A full binary tree is defined as a binary tree in which all nodes have either zero or two child nodes. Conversely, there is no node in a full binary tree, which has one child node.
For Example :
To check whether a binary tree is a full binary tree we need to test the following cases:-
1) If a binary tree node is NULL then it is a full binary tree.
2) If a binary tree node does have empty left and right sub-trees, then it is a full binary tree by definition.
3) If a binary tree node has left and right sub-trees, then it is a part of a full binary tree by definition. In this case recursively check if the left and right sub-trees are also binary trees themselves.
4) In all other combinations of right and left sub-trees, the binary tree is not a full binary tree.
Following is the implementation for checking if a binary tree is a full binary tree.
class Node { int data; Node left, right; Node(int item) { data = item; left = right = null; } } class BinaryTree { Node root; /* this function checks if a binary tree is full or not */ boolean isFullTree(Node node) { // if empty tree if(node == null) return true; // if leaf node if(node.left == null && node.right == null ) return true; // if both left and right subtrees are not null // the are full if((node.left!=null) && (node.right!=null)) return (isFullTree(node.left) && isFullTree(node.right)); // if none work return false; } // Driver program public static void main(String args[]) { BinaryTree tree = new BinaryTree(); tree.root = new Node(10); tree.root.left = new Node(20); tree.root.right = new Node(30); tree.root.left.right = new Node(40); tree.root.left.left = new Node(50); tree.root.right.left = new Node(60); tree.root.left.left.left = new Node(80); tree.root.right.right = new Node(70); tree.root.left.left.right = new Node(90); tree.root.left.right.left = new Node(80); tree.root.left.right.right = new Node(90); tree.root.right.left.left = new Node(80); tree.root.right.left.right = new Node(90); tree.root.right.right.left = new Node(80); tree.root.right.right.right = new Node(90); if(tree.isFullTree(tree.root)) System.out.print("The binary tree is full"); else System.out.print("The binary tree is not full"); } } // This code is contributed by Mayank Jaiswal
Check whether a binary tree is a full binary tree or not
标签：art class work main nod function eth alt let
原文地址：https://www.cnblogs.com/codingyangmao/p/11578439.html
