There's an alphabet of size $$$k$$$. For a string $$$S$$$ in this alphabet (the text), and string $$$P$$$ (the pattern), let $$$F(S,P) = $$$ the maximum number of non-overlapping substrings you can take in $$$S$$$, that are equal to $$$P$$$.
Let's call a string $$$Q$$$ beautiful, if each letter in it occurs no more than $$$2$$$ times.
Over all possible strings of size $$$n$$$, and all possible beautiful patterns $$$P$$$ of size $$$m$$$, calculate the sum of $$$F(S,P)$$$. Because this sum can be huge, output the result modulo $$$10^9 + 7$$$.
The first and only line of the input contains $$$3$$$ integers, $$$n,m,k$$$ ($$$1 \leq n \leq 10^6$$$, $$$1 \leq m \leq 2000$$$, $$$m \leq n$$$ and $$$1 \leq k \leq 10^9$$$) — respectively, the length of string $$$S$$$, the length of the pattern $$$P$$$ and the alphabet size.
Print a single line, containing one integer — the sum of $$$F(S,P)$$$ over all strings $$$S$$$ and beautiful strings $$$P$$$ modulo $$$10^9 + 7$$$.
4 2 3
228
999999 1999 12345678
52352722
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