TreeTraversalsExample.java

package ch14;

public class TreeTraversalsExample {
 static class TNode {
 char val;
 TNode left;
 TNode right;

 public TNode(char val) {
 this.val = val;
 }

 public TNode(char val, TNode left, TNode right) {
 this.val = val;
 this.left = left;
 this.right = right;
 }
 }

 public static void preorder(TNode node) {
 if (node == null)
 return;
 System.out.printf("%c ", node.val);
 preorder(node.left);
 preorder(node.right);
 }

 public static void inorder(TNode node) {
 if (node == null)
 return;
 inorder(node.left);
 System.out.printf("%c ", node.val);
 inorder(node.right);
 }

 public static void postorder(TNode node) {
 if (node == null)
 return;
 postorder(node.left);
 postorder(node.right);
 System.out.printf("%c ", node.val);
 }

 public static void main(String[] args) {
 // 그림 14-26 예제 트리 생성
 TNode root = new TNode('F',
 new TNode('B',
 new TNode('A'),
 new TNode('D',
 new TNode('C'), new TNode('E'))
 ),
 new TNode('G',
 null,
 new TNode('I',
 new TNode('H'), null))
 );

 // 전위 순회
 preorder(root);
 System.out.println();
 // 중위 순회
 inorder(root);
 System.out.println();
 // 후위 순회
 postorder(root);
 System.out.println();
 }
}