Petya got some unusual dice as a gift: each die has 26 faces containing all 26 small letters of the English alphabet, one letter on each face. Petya wanted to play a game: initially, he arranged $$$n$$$ dice in a row, forming a certain string, and now he wants to turn it into his favorite string. To do this, Petya makes moves: in one move, Petya can flip any die, changing the corresponding letter of the string to any other. Petya also has a big fluffy Cat who can make moves instead of him. Depending on the Cat's mood, it can help Petya by immediately flipping the dice to form Petya's favorite string in one move, or the Cat can do the opposite: flip the dice so that the resulting string differs from Petya's favorite string in every letter. A move by any player is possible only if it somehow changes the string of dice. The players can make moves in any order.
Since Petya needs to give a report on physical education, there is time only for $$$m$$$ moves in the game. Petya now wonders how many different games can occur if after exactly $$$m$$$ moves, the dice should form his favorite string. Since the number of games can be very large, Petya is only interested in the remainder of dividing this number by $$$9! = 362\,880$$$. Help Petya find this value.
Note that two games are different if there is a move number that Petya made in one game, and the Cat made in the other, or if there is a move number after which the strings on the dice were different.
The first line contains two integers $$$n$$$ and $$$m$$$ ($$$1 \leq n \leq 10\,000$$$ and $$$0 \leq m \leq 10\,000$$$). The second line contains the initial string that was obtained from the dice before the start of the game, and the third line contains Petya's favorite string. It is guaranteed that both strings have a length of $$$n$$$ and consist only of small letters of the English alphabet.
Output a single integer: the answer to the problem.
4 5starwars
111957
4 1spbuspbu
0
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