A15792. Sum on Subarrays
编程题
普及/提高-
知识点
题目描述
For an array $a = [a_1, a_2, \dots, a_n]$ , let's denote its subarray $a[l, r]$ as the array $[a_l, a_{l+1}, \dots, a_r]$ .
For example, the array $a = [1, -3, 1]$ has $6$ non-empty subarrays:
- $a[1,1] = [1]$ ;
- $a[1,2] = [1,-3]$ ;
- $a[1,3] = [1,-3,1]$ ;
- $a[2,2] = [-3]$ ;
- $a[2,3] = [-3,1]$ ;
- $a[3,3] = [1]$ .
You are given two integers $n$ and $k$ . Construct an array $a$ consisting of $n$ integers such that:
- all elements of $a$ are from $-1000$ to $1000$ ;
- $a$ has exactly $k$ subarrays with positive sums;
- the rest $\dfrac{(n+1) \cdot n}{2}-k$ subarrays of $a$ have negative sums.
For example, the array $a = [1, -3, 1]$ has $6$ non-empty subarrays:
- $a[1,1] = [1]$ ;
- $a[1,2] = [1,-3]$ ;
- $a[1,3] = [1,-3,1]$ ;
- $a[2,2] = [-3]$ ;
- $a[2,3] = [-3,1]$ ;
- $a[3,3] = [1]$ .
You are given two integers $n$ and $k$ . Construct an array $a$ consisting of $n$ integers such that:
- all elements of $a$ are from $-1000$ to $1000$ ;
- $a$ has exactly $k$ subarrays with positive sums;
- the rest $\dfrac{(n+1) \cdot n}{2}-k$ subarrays of $a$ have negative sums.
输入格式
The first line contains one integer $t$ ( $1 \le t \le 5000$ ) — the number of test cases.
Each test case consists of one line containing two integers $n$ and $k$ ( $2 \le n \le 30$ ; $0 \le k \le \dfrac{(n+1) \cdot n}{2}$ ).
Each test case consists of one line containing two integers $n$ and $k$ ( $2 \le n \le 30$ ; $0 \le k \le \dfrac{(n+1) \cdot n}{2}$ ).
输出格式
For each test case, print $n$ integers — the elements of the array meeting the constraints. It can be shown that the answer always exists. If there are multiple answers, print any of them.
输入输出样例
输入 #1
4 3 2 2 0 2 2 4 6
输出 #1
1 -3 1 -13 -42 -13 42 -3 -4 10 -2