//输入两个二叉树，判断A是不是B的子树
       public  boolean  hasSubTree(BitNode root1,BitNode root2){
            boolean result=false;
            if(root1!=null&&root2!=null){
               if(root1.data==root2.data){
                       result=doesTree1HavaTree2(root1,root2);
                   if(!result)
                       result=hasSubTree(root1.lchild,root2);
                   if (!result)
                       result=hasSubTree(root1.rchild,root2);
               }
            }
            return  result;

       }

       private  boolean doesTree1HavaTree2(BitNode root1,BitNode root2) {
           if (root2 == null) {
               return true;
           } else if (root1 == null) {
               return false;
           }
           if (root1.data != root2.data) {
               return false;
           }
           return  doesTree1HavaTree2(root1.lchild,root2.lchild)&&doesTree1HavaTree2(root1.rchild,root2.rchild);
       }