Statement : C. Interval Mod
You are given an array $a$ consisting of $n$ integers, as well as a parameter $k$ and an integer set $M=\{p, q\}$.
You can perform the following operation on $a$ an arbitrary number of times (possibly zero):
- First, choose an interval $[l,r]$ ($1 \le l \le r \le n$) of length at least $k$ (i.e., $r-l+1\ge k$) and an integer $m \in M$;
- Then, set $a_i \gets a_i \bmod m$ for each $l \le i \le r$.
You have to find the minimum possible value of $\sum \limits_{i=1}^n a_i$ after all operations.
Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1 \le t \le 10^4$). The description of the test cases follows.
The first line of each test case contains four integers $n$, $k$, $p$, and $q$ ($1\le k\le n\le 10^5$, $1\le p \lt q\le 10^9$) — the length of $a$, the parameter, and the elements of $M$.
The second line contains $n$ integers $a_1, a_2, \ldots, a_n$ ($1\le a_i\le 10^9$) — the elements of $a$.
It is guaranteed that the sum of $n$ over all test cases does not exceed $10^5$.
For each test case, output a single integer — the minimum possible value of $\sum \limits_{i=1}^n a_i$ after all operations.
Input
6
1 1 3 4
2026
3 2 10 20
31 41 59
4 3 3 4
1 2 3 4
6 4 9 20
18 27 180 9 45 99
7 4 3 5
6 7 14 12 100 78 4
9 4 244 353
9982 4435 3998 2443 5399 8244 3539 9824 4353
Output
1
11
3
0
4
569
Note
In the second test case, a possible way to obtain $\sum \limits_{i=1}^n a_i=11$ is to apply the following operation to $a$:
- Choose $[l,r]=[1,4]$ and $m=10$, then $a$ becomes $[1,1,9]$.
In the third test case, a possible way to obtain $\sum \limits_{i=1}^n a_i=3$ is to apply the following operations to $a$:
- Choose $[l,r]=[1,4]$ and $m=4$, then $a$ becomes $[1,2,3,0]$;
- Choose $[l,r]=[2,4]$ and $m=3$, then $a$ becomes $[1,2,0,0]$.