Java 两结点的最近公共祖先结点

public class Main {public static void main(String[] args) throws Exception {BinaryTreeNode root = new BinaryTreeNode();BinaryTreeNode n1 = new BinaryTreeNode();BinaryTreeNode n2 = new BinaryTreeNode();BinaryTreeNode n3 = new BinaryTreeNode();BinaryTreeNode n4 = new BinaryTreeNode();BinaryTreeNode n5 = new BinaryTreeNode();root.value = 50;n1.value = 25;n2.value = 75;n3.value = 10;n4.value = 35;n5.value = 35;root.leftNode = n1;root.rightNode = n2;n1.leftNode = n3;n1.rightNode = n4;System.out.println(findNode(root,n1,n5).value);}//找到两个结点的最近公共祖先public static BinaryTreeNode findNode(BinaryTreeNode root, BinaryTreeNode node1, BinaryTreeNode node2){List<BinaryTreeNode> path1 = new ArrayList<BinaryTreeNode>();List<BinaryTreeNode> path2 = new ArrayList<BinaryTreeNode>();boolean flag1 = false;boolean flag2 = false;flag1 = getPath(root,node1,path1);flag2 = getPath(root,node2,path2);if(flag1 == false || flag2 == false){return null;}return findCommonNode(path1,path2);}//找到目标结点的路径public static boolean getPath(BinaryTreeNode root, BinaryTreeNode node, List<BinaryTreeNode> path){if(root!=null){path.add(root);}if(node == root){return true;}if(root == null){return false;}boolean found = getPath(root.leftNode,node,path);if(!found){found = getPath(root.rightNode, node,path);}if(!found){path.remove(path.size()-1);}return found;}//找到两条路径的最后一个相同的结点public static BinaryTreeNode findCommonNode(List<BinaryTreeNode> path1, List<BinaryTreeNode> path2){BinaryTreeNode result = path1.get(0);int temp = 0;while(temp<path1.size() && temp<path2.size() && path1.get(temp) == path2.get(temp)){result = path1.get(temp);temp++;}return result;}}