codeforces#P1622C. Set or Decrease
Set or Decrease
Description
You are given an integer array $a_1, a_2, \dots, a_n$ and integer $k$.
In one step you can
- either choose some index $i$ and decrease $a_i$ by one (make $a_i = a_i - 1$);
- or choose two indices $i$ and $j$ and set $a_i$ equal to $a_j$ (make $a_i = a_j$).
What is the minimum number of steps you need to make the sum of array $\sum\limits_{i=1}^{n}{a_i} \le k$? (You are allowed to make values of array negative).
The first line contains a single integer $t$ ($1 \le t \le 10^4$) — the number of test cases.
The first line of each test case contains two integers $n$ and $k$ ($1 \le n \le 2 \cdot 10^5$; $1 \le k \le 10^{15}$) — the size of array $a$ and upper bound on its sum.
The second line of each test case contains $n$ integers $a_1, a_2, \dots, a_n$ ($1 \le a_i \le 10^9$) — the array itself.
It's guaranteed that the sum of $n$ over all test cases doesn't exceed $2 \cdot 10^5$.
For each test case, print one integer — the minimum number of steps to make $\sum\limits_{i=1}^{n}{a_i} \le k$.
Input
The first line contains a single integer $t$ ($1 \le t \le 10^4$) — the number of test cases.
The first line of each test case contains two integers $n$ and $k$ ($1 \le n \le 2 \cdot 10^5$; $1 \le k \le 10^{15}$) — the size of array $a$ and upper bound on its sum.
The second line of each test case contains $n$ integers $a_1, a_2, \dots, a_n$ ($1 \le a_i \le 10^9$) — the array itself.
It's guaranteed that the sum of $n$ over all test cases doesn't exceed $2 \cdot 10^5$.
Output
For each test case, print one integer — the minimum number of steps to make $\sum\limits_{i=1}^{n}{a_i} \le k$.
Samples
4
1 10
20
2 69
6 9
7 8
1 2 1 3 1 2 1
10 1
1 2 3 1 2 6 1 6 8 10
10
0
2
7
Note
In the first test case, you should decrease $a_1$ $10$ times to get the sum lower or equal to $k = 10$.
In the second test case, the sum of array $a$ is already less or equal to $69$, so you don't need to change it.
In the third test case, you can, for example:
- set $a_4 = a_3 = 1$;
- decrease $a_4$ by one, and get $a_4 = 0$.
In the fourth test case, you can, for example:
- choose $a_7$ and decrease in by one $3$ times; you'll get $a_7 = -2$;
- choose $4$ elements $a_6$, $a_8$, $a_9$ and $a_{10}$ and them equal to $a_7 = -2$.