Problem Statement
You are given a multiset of integers with $N$ elements: $A=\lbrace A_1,A_2,...,A_N \rbrace$. It is guaranteed that every element of $A$ is between $1$ and $M$ (inclusive).
Let us repeat the following operation $K$ times.
- Choose an integer between
$1$and$M$(inclusive) and add it to$A$. Then, delete the$X$-th smallest value in$A$.
Here, the $X$-th smallest value in $A$ is the $X$-th value from the front in the sequence of the elements of $A$ sorted in non-decreasing order.
There are $M^K$ ways to choose an integer $K$ times between $1$ and $M$. Assume that, for each of these ways, we have found the sum of the elements of $A$ after the operations with the corresponding choices. Find the sum, modulo $998244353$, of the $M^K$ values computed.
Constraints
$1 \le N,M,K \le 2000$$1 \le X \le N+1$$1 \le A_i \le M$- All values in input are integers.
Input
Input is given from Standard Input in the following format:
N M K X
A_1 A_2 \dots A_N
Output
Print the answer.
样例
2 4 2 1
1 3
99
5 9 6 3
3 7 1 9 9
15411789
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