二叉树最近公共父节点

有一个普通二叉树，AB分别为两个子节点，求AB最近的公共父节点。

 1 import java.util.ArrayList;

 2 import java.util.List;

 3 

 4 

 5 public class Node {

 6 

 7     Node leftChild;

 8     Node rightChild;

 9     int data;

10     

11     public Node(Node leftChild,Node rightChild,int data){

12         this.leftChild = leftChild;

13         this.rightChild = rightChild;

14         this.data = data;

15     }

16     

17     public boolean getPath(Node root,Node decNode,List<Node> array){

18         boolean findResult = false;

19         if(null != root){

20             if(root == decNode){

21                 array.add(root);

22                 findResult = true;

23             }

24             if(!findResult&& root.leftChild!=null){

25                 findResult = this.getPath(root.leftChild, decNode, array);

26                 if(findResult){

27                     array.add(root);

28                 }

29             }

30             if(!findResult&& root.rightChild!=null){

31                 findResult = this.getPath(root.rightChild, decNode, array);

32                 if(findResult){

33                     array.add(root);

34                 }

35             }

36         }

37         return findResult;

38     }

39     

40     static Node getCommonRoot(Node root,Node a,Node b){

41         Node common = null;

42         List<Node> pathA = new ArrayList<Node>();

43         List<Node> pahtB = new ArrayList<Node>();

44         a.getPath(root, a, pathA);

45         b.getPath(root, b, pahtB);

46         for(Node NodeA:pathA){

47             for(Node NodeB:pahtB){

48                 if(NodeA == NodeB){

49                     common = NodeA;

50                     break;

51                 }

52             }

53             if(null!=common){

54                 break;

55             }

56         }

57         return common;

58     }

59     

60     /**

61      * @param args

62      */

63     public static void main(String[] args) {

64         

65         Node g = new Node(null,null,7);

66         Node f = new Node(null,null,6);

67         Node e = new Node(null,null,5);

68         Node d = new Node(null,null,4);

69         Node c = new Node(f,g,3);

70         Node b = new Node(d,e,2);

71         Node a = new Node(b,c,1); 

72         

73         Node test=null;

74         test = getCommonRoot(a,b,f);

75         if(null!=test){

76             System.out.println(test.data);

77         }

78     }

79 

80 }