package println algo ret linked nts charles right per

package com.charles.algorithm;

import java.util.LinkedList;
import java.util.Queue;

public class Tree {

private Queue<TreeNode> elements = new LinkedList<TreeNode>();

public static void main(String[] args) {

/*
* @desc: construct a tree:
* root
* A B

* C D E F
* G H I J
*/

TreeNode root = new TreeNode("root");

TreeNode A = new TreeNode("A");
TreeNode B = new TreeNode("B");
TreeNode C = new TreeNode("C");
TreeNode D = new TreeNode("D");
TreeNode E = new TreeNode("E");
TreeNode F = new TreeNode("F");

TreeNode G = new TreeNode("G");
TreeNode H = new TreeNode("H");
TreeNode I = new TreeNode("I");
TreeNode J = new TreeNode("J");

root.setLeft(A);
root.setRight(B);
A.setLeft(C);
A.setRight(D);
B.setLeft(E);
B.setRight(F);
C.setLeft(G);
C.setRight(H);
D.setLeft(I);
D.setRight(J);

Tree tree = new Tree();

tree.broadTraval(root);
}

public void broadTraval(TreeNode root) {

if (null != root) {
elements.add(root);
} else {
return;
}

while (0 < elements.size()) {
root = elements.poll();
System.out.println(root.getData());
if (null != root.getLeft()) {
elements.add(root.getLeft());
}
if (null != root.getRight()) {
elements.add(root.getRight());
}
}
}
}

class TreeNode {
/*
* @Desc: define a tree node
*/

private String data;
private TreeNode left;
private TreeNode right;

public TreeNode() {
}

public TreeNode(String data) {
super();
this.data = data;
}

public String getData() {
return data;
}

public void setData(String data) {
this.data = data;
}

public TreeNode getLeft() {
return left;
}

public void setLeft(TreeNode left) {
this.left = left;
}

public TreeNode getRight() {
return right;
}

public void setRight(TreeNode right) {
this.right = right;
}
}

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