java二叉树

import java.util.ArrayList;

public class Solution {

    public boolean HasSubtree(TreeNode root1,TreeNode root2) {
        boolean result = false;
        if(root1!=null && root2!=null){
            result = doesTree1HaveTree2(root1, root2);
            if(!result){
                result = HasSubtree(root1.left, root2);
            }
            if(!result){
                result = HasSubtree(root1.right, root2);
            }
        }
        return result;
    }

    private boolean doesTree1HaveTree2(TreeNode root1,TreeNode root2){
        if(root2==null){
            return true;
        }
        if(root1==null){
            return false;
        }
        if(root1.val!=root2.val){
            return false;
        }
        return doesTree1HaveTree2(root1.left, root2.left)&&doesTree1HaveTree2(root1.right,root2.right);
    }

    public TreeNode generateTreeByArray(char[] array){
        ArrayList<TreeNode> treeNodes = new ArrayList<>();
        if(array==null || array.length<=0 || array[0]=='#'){
            return null;
        }
        TreeNode treeNode = new TreeNode(array[0]-'0');
        treeNodes.add(treeNode);
        int indexParent = 0;
        int indexChild = 1;
        while(indexChild<array.length){
            if(treeNodes.get(indexParent)!=null){
                if(array[indexChild]!='#'){
                    treeNodes.get(indexParent).left = new TreeNode(array[indexChild]-'0');
                    treeNodes.add(treeNodes.get(indexParent).left);
                }
                if(indexChild+1<array.length && array[indexChild+1]!='#'){
                    treeNodes.get(indexParent).right = new TreeNode(array[indexChild+1]-'0');
                    treeNodes.add(treeNodes.get(indexParent).right);
                }
                indexParent++;
                indexChild+=2;
            }
        }
        return treeNode;
    }

    public static void main(String[] args) {
        Solution solution = new Solution();
        char[] array = {'8','8','7','9','2','#','#','#','#','4','7'};
        TreeNode treeNode = solution.generateTreeByArray(array);
        char[] array1 = {'8','9','2'};
        TreeNode treeNode1 = solution.generateTreeByArray(array1);
        boolean flag = solution.HasSubtree(treeNode, treeNode1);
        System.out.println();
    }
}

class TreeNode{
    int val = 0;
    TreeNode left = null;
    TreeNode right = null;
    TreeNode(int k){
        val = k;
    }
}