判断Tree2是否是Tree1的子树
题目：Tree1 and Tree2 are both binary trees nodes having value, determine if Tree2 is a subtree of tree1.
bool matchTree(TreeNode *roo1,TreeNode *root2){if(root1 == NULL && root2 == NULL)return true;if(root1 == NULL || root2 == NULL)return false;if(root1->val != root2->val)return false;return matchTree(root1->left,root2->left) && matchTree(root1->right,root2->right);
}bool subTree(TreeNode *root1,TreeNode *root2){if(root2 == NULL)return true;if(root1 == NULL)return false;if(root1->val == root2->val){if(matchTree(root1,root2))return true;}return subTree(root1->left,root2) || subTree(root1->right,root2);
}