金山云Java方向9.16笔试

public class Main {
    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
        while (in.hasNext())
        {
            int n=in.nextInt();
            if(n<0)
            {
                System.out.println(0);
                continue;
            }
            long[] nums=new long[n];
            long pre=0;
            nums[0]=1;
            for(int i=1;i<n;i++)
            {
                nums[i]=nums[i-1]+pre;
                pre=nums[i-1];
            }
            for(int i=0;i<n;i++)
            {
                for(int j=0;j<=i;j++)
                {
                    System.out.print(nums[j]+" ");
                }
                for(int k=i-1;k>=0;k--)
                {
                    System.out.print(nums[k]+" ");
                }
                System.out.println();
            }
        }
    }
}

public class Main {
    static class TreeNode{
        public int val;
        public TreeNode left;
        public TreeNode right;
        public TreeNode(int val)
        {
            this.val=val;
        }
    }

    static TreeNode p=new TreeNode(-1);
    static TreeNode q=new TreeNode(-1);
    static int pVal;
    static int qVal;
    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
        while (in.hasNextLine())
        {
            String id=in.nextLine();
            if(id==null || id.equals(""))
            {
                System.out.println(-1);
                continue;
            }
            String[] ids = id.split(" ");
            LinkedList<Integer> queue=new LinkedList<>();
            for(int i=0;i<ids.length;i++)
            {
                queue.offer(Integer.valueOf(ids[i]));
            }
            String virus=in.nextLine();
            String[] viruses = virus.split(" ");
            pVal=Integer.valueOf(viruses[0]);
            qVal=Integer.valueOf(viruses[1]);
            TreeNode root=bulidTree(queue);
            TreeNode res=getRes(root);
            if(res==null)
            {
                System.out.println(-1);
            }else
            {
                System.out.println(res.val);
            }
        }
    }

    private static TreeNode getRes(TreeNode root) {
        if(root==null || root==p || root==q) return root;
        TreeNode left=getRes(root.left);
        TreeNode right=getRes(root.right);

        if(left==null) return  right;
        if(right==null) return left;
        return root;
    }

    private static TreeNode bulidTree(LinkedList<Integer> queue) {
        int val=queue.poll();
        if(val==-1)
        {
            return null;
        }
        TreeNode root=new TreeNode(val);
        if(pVal==root.val)
        {
            p=root;
        }
        if(qVal==root.val)
        {
            q=root;
        }
        root.left=bulidTree(queue);
        root.right=bulidTree(queue);
        return root;
    }
}