Problem10952--ABC367 - G - Sum of (XOR^K or 0)

10952: ABC367 - G - Sum of (XOR^K or 0)

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

You are given positive integers $N$, $M$, $K$, and a sequence of non-negative integers: $A=(A_1,A_2,\ldots,A_N)$.

For a non-empty non-negative integer sequence $B=(B_1,B_2,\ldots,B_{|B|})$, we define its score as follows.

  • If the length of $B$ is a multiple of $M$: $(B_1 \oplus B_2 \oplus \dots \oplus B_{|B|})^K$
  • Otherwise: $0$

Here, $\oplus$ represents the bitwise XOR.

Find the sum, modulo $998244353$, of the scores of the $2^N-1$ non-empty subsequences of $A$.

>>>What is bitwise XOR?<<< The bitwise XOR of non-negative integers $A$ and $B$, denoted as $A \oplus B$, is defined as follows:
  • In the binary representation of $A \oplus B$, the digit at position $2^k$ ($k \geq 0$) is $1$ if exactly one of $A$ and $B$ has a $1$ in that position in their binary representations, and $0$ otherwise.
For example, $3 \oplus 5 = 6$ (in binary: $011 \oplus 101 = 110$).
In general, the XOR of $k$ integers $p_1, \dots, p_k$ is defined as $(\cdots ((p_1 \oplus p_2) \oplus p_3) \oplus \cdots \oplus p_k)$, and it can be proved that this is independent of the order of $p_1, \dots, p_k$.

Input

The input is given from Standard Input in the following format:

```
$N$ $M$ $K$
$A_1$ $A_2$ $\ldots$ $A_N$
```

Output

Print the answer.

Constraints

-   $1 \leq N,K \leq 2 \times 10^5$
-   $1 \leq M \leq 100$
-   $0 \leq A_i &lt; 2^{20}$
-   All input values are integers.

Sample 1 Input

3 2 2
1 2 3

Sample 1 Output

14

Here are the scores of the $2^3-1=7$ non-empty subsequences of $A$.

  • $(1)$: $0$
  • $(2)$: $0$
  • $(3)$: $0$
  • $(1,2)$: $(1\oplus2)^2=9$
  • $(1,3)$: $(1\oplus3)^2=4$
  • $(2,3)$: $(2\oplus3)^2=1$
  • $(1,2,3)$: $0$

Therefore, the sought sum is $0+0+0+9+4+1+0=14$.

Sample 2 Input

10 5 3
100 100 100 100 100 100 100 100 100 100

Sample 2 Output

252000000

Sample 3 Input

16 4 100
7053 3876 3178 8422 7802 5998 2334 6757 6889 6637 7365 9495 7848 9026 7312 6558

Sample 3 Output

432440016

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