CF1508B.Almost Sorted

普及/提高-

通过率:0%

AC君温馨提醒

该题目为【codeforces】题库的题目,您提交的代码将被提交至codeforces进行远程评测,并由ACGO抓取测评结果后进行展示。由于远程测评的测评机由其他平台提供,我们无法保证该服务的稳定性,若提交后无反应,请等待一段时间后再进行重试。

题目描述

Seiji Maki doesn't only like to observe relationships being unfolded, he also likes to observe sequences of numbers, especially permutations. Today, he has his eyes on almost sorted permutations.

A permutation a1,a2,,ana_1, a_2, \dots, a_n of 1,2,,n1, 2, \dots, n is said to be almost sorted if the condition ai+1ai1a_{i + 1} \ge a_i - 1 holds for all ii between 11 and n1n - 1 inclusive.

Maki is considering the list of all almost sorted permutations of 1,2,,n1, 2, \dots, n , given in lexicographical order, and he wants to find the kk -th permutation in this list. Can you help him to find such permutation?

Permutation pp is lexicographically smaller than a permutation qq if and only if the following holds:

  • in the first position where pp and qq differ, the permutation pp has a smaller element than the corresponding element in qq .

输入格式

The first line contains a single integer tt ( 1t10001\le t\le 1000 ) — the number of test cases.

Each test case consists of a single line containing two integers nn and kk ( 1n1051 \le n \le 10^5 , 1k10181 \le k \le 10^{18} ).

It is guaranteed that the sum of nn over all test cases does not exceed 10510^5 .

输出格式

For each test case, print a single line containing the kk -th almost sorted permutation of length nn in lexicographical order, or 1-1 if it doesn't exist.

输入输出样例

  • 输入#1

    5
    1 1
    1 2
    3 3
    6 5
    3 4

    输出#1

    1 
    -1
    2 1 3 
    1 2 4 3 5 6 
    3 2 1

说明/提示

For the first and second test, the list of almost sorted permutations with n=1n = 1 is {[1]}\{[1]\} .

For the third and fifth test, the list of almost sorted permutations with n=3n = 3 is {[1,2,3],[1,3,2],[2,1,3],[3,2,1]}\{[1, 2, 3], [1, 3, 2], [2, 1, 3], [3, 2, 1]\} .

首页