Problem9321--ABC297 —— F - Minimum Bounding Box 2

9321: ABC297 —— F - Minimum Bounding Box 2

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

We have a grid with $H$ rows and $W$ columns.

We choose $K$ cells in this grid uniformly at random. The score is the number of cells in the minimum rectangle (whose edges are parallel to the axes of the grid) that contains all of the chosen cells.

Find the expected score modulo $998244353$.

What is rational number modulo $998244353$? We can prove that the sought expected value is always a rational number. Moreover, under the Constraints of this problem, when the value is represented as $\frac{P}{Q}$ by two coprime integers $P$ and $Q$, we can prove that there is a unique integer $R$ such that $R \times Q \equiv P\pmod{998244353}$ and $0 \leq R \lt 998244353$. Find such $R$.

Input

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

```
$H$ $W$ $K$
```

Output

Print the answer.

Constraints

$1\leq H,W \leq 1000$
$1\leq K \leq HW$
All values in the input are integers.

Sample 1 Input

2 2 2

Sample 1 Output

665496238
The score equals 4 in the following two cases: if cells (1,1) and (2,2) are chosen, or cells (1,2) and (2,1) are chosen. The other four cases yield a score of 2.
Thus, the expected score equals $\frac{4×2+2×4}{6}=\frac{8}{3}$. Since $665496238×3≡8(\bmod\ {998244353})$, you should print 665496238.

Sample 2 Input

10 10 1

Sample 2 Output

1

Sample 3 Input

314 159 2653

Sample 3 Output

639716353

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