class TreeNode {
  int val = 0;
  TreeNode left = null;
  TreeNode right = null;

  public TreeNode(int val) {
    this.val = val;

  }
}

public static boolean HasSubtree2(TreeNode root1, TreeNode root2) {

    if (root2 == null)
      return false;
    String str = "";
    Stack<TreeNode> stack = new Stack<TreeNode>();
    stack.push(null);
    stack.push(root1);
    TreeNode node = null;
    while ((node = stack.pop()) != null) {
      str += '_' + node.val + '_';

      if (node.right != null) {
        stack.push(node.right);
      }
      if (node.left != null) {
        stack.push(node.left);
      }
    }

    String str2 = "";
    node = null;
    stack.push(null);
    stack.push(root2);
    while ((node = stack.pop()) != null) {
      str2 += '_' + node.val + '_';

      if (node.right != null) {
        stack.push(node.right);
      }
      if (node.left != null) {
        stack.push(node.left);
      }
    }

    if (str.contains(str2)) {
      return true;
    } else {
      return false;
    }
  }

public static TreeNode getTree(int[] node, int index) {

    if (index >= node.length)
      return null;
    TreeNode n = null;
    if (node[index] != -1) {
      n = new TreeNode(node[index]);
      n.left = getTree(node, index * 2 + 1);
      n.right = getTree(node, index * 2 + 2);
    }
    return n;
  }

import java.util.Stack;

public class HasSubtree {

  public static void main(String[] args) {

    TreeNode tree = getTree(new int[] { 8, 8, 7, 9, 2, -1, -1, -1, -1, 4, 7 }, 0);
    TreeNode tree2 = getTree(new int[] { 2, 4, 7 }, 0);
    boolean bool = HasSubtree(tree, tree2);
    System.out.println(bool);

    boolean bool2 = HasSubtree2(tree, tree2);
    System.out.println(bool2);
  }

  public static boolean HasSubtree2(TreeNode root1, TreeNode root2) {

    if (root2 == null)
      return false;
    String str = "";
    Stack<TreeNode> stack = new Stack<TreeNode>();
    stack.push(null);
    stack.push(root1);
    TreeNode node = null;
    while ((node = stack.pop()) != null) {
      str += '_' + node.val + '_';

      if (node.right != null) {
        stack.push(node.right);
      }
      if (node.left != null) {
        stack.push(node.left);
      }
    }

    String str2 = "";
    node = null;
    stack.push(null);
    stack.push(root2);
    while ((node = stack.pop()) != null) {
      str2 += '_' + node.val + '_';

      if (node.right != null) {
        stack.push(node.right);
      }
      if (node.left != null) {
        stack.push(node.left);
      }
    }

    if (str.contains(str2)) {
      return true;
    } else {
      return false;
    }
  }

  public static TreeNode getTree(int[] node, int index) {

    if (index >= node.length)
      return null;
    TreeNode n = null;
    if (node[index] != -1) {
      n = new TreeNode(node[index]);
      n.left = getTree(node, index * 2 + 1);
      n.right = getTree(node, index * 2 + 2);
    }
    return n;
  }

  public static boolean HasSubtree(TreeNode root1, TreeNode root2) {

    boolean result = false;
    if (root1 != null && root2 != null) {

      if (root1.val == root2.val) {
        result = isSubTree(root1, root2);
      }

      if (!result) {
        result = isSubTree(root1.left, root2);
      }

      if (!result) {
        result = isSubTree(root1.right, root2);
      }
    }

    return result;
  }

  private static boolean isSubTree(TreeNode root1, TreeNode root2) {

    if (root1 == null)
      return false;
    if (root2 == null)
      return true;
    if (root1.val != root2.val)
      return false;

    return isSubTree(root1.left, root2.left)
        && isSubTree(root1.right, root2.right);
  }

}

class TreeNode {
  int val = 0;
  TreeNode left = null;
  TreeNode right = null;

  public TreeNode(int val) {
    this.val = val;

  }

}