Codeforces Round #624 (Div. 3) E. Construct the Binary Tree(模拟二叉树)

Description:
You are given two integers nnn and ddd. You need to construct a rooted binary tree consisting of n vertices with a root at the vertex 111 and the sum of depths of all vertices equals to ddd.

A tree is a connected graph without cycles. A rooted tree has a special vertex called the root. A parent of a vertex vvv is the last different from v vertex on the path from the root to the vertex v. The depth of the vertex vvv is the length of the path from the root to the vertex vvv. Children of vertex v are all vertices for which v is the parent. The binary tree is such a tree that no vertex has more than 222 children.

You have to answer t independent test cases.

Input
The first line of the input contains one integer t(1≤t≤1000)t (1≤t≤1000)t(1≤t≤1000) — the number of test cases.

The only line of each test case contains two integers nnn and d(2≤n,d≤5000)d (2≤n,d≤5000)d(2≤n,d≤5000)— the number of vertices in the tree and the required sum of depths of all vertices.

It is guaranteed that the sum of nnn and the sum of ddd both does not exceed 500050005000 (∑n≤5000,∑d≤5000)(∑n≤5000,∑d≤5000)(∑n≤5000,∑d≤5000).

Output
For each test case, print the answer.

If it is impossible to construct such a tree, print “NO” (without quotes) in the first line. Otherwise, print “{YES}” in the first line. Then print n−1 integers p2,p3,…,pn in the second line, where pi is the parent of the vertex i. Note that the sequence of parents you print should describe some binary tree.

Example
input

3
5 7
10 19
10 18
1
2
3
4
output
YES
1 2 1 3
YES
1 2 3 3 9 9 2 1 6
NO
1
2
3
4
5
Note
Pictures corresponding to the first and the second test cases of the example:
Codeforces Round #624 (Div. 3) E. Construct the Binary Tree(模拟二叉树)_第1张图片
思路
给定t组数据,每组数据限定n个结点和深度和d
求能否构成二叉树且节点深度和是否等于d
满足并输出每个节点的深度

首先节点全在一条分支上深度和最大,然后在此状态上将后面的点前移动
,每次移动更新完判断是否能够满足条件
进行构造即可

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