2536.Puzzle Lover

Time Limit: 1s Memory Limit: 256MB

Oleg Petrov loves crossword puzzles and every Thursday he buys his favorite magazine with crosswords and other word puzzles. In the last magazine Oleg found a curious puzzle, and the magazine promised a valuable prize for it's solution. We give a formal description of the problem below.

The puzzle field consists of two rows, each row contains n cells. Each cell contains exactly one small English letter. You also are given a word w, which consists of k small English letters. A solution of the puzzle is a sequence of field cells c1, ..., ck, such that:
For all i from 1 to k the letter written in the cell ci matches the letter wi; All the cells in the sequence are pairwise distinct; For all i from 1 to k-1 cells ci and ci+1 have a common side.
Oleg Petrov quickly found a solution for the puzzle. Now he wonders, how many distinct solutions are there for this puzzle. Oleg Petrov doesn't like too large numbers, so calculate the answer modulo 109+7.

Two solutions ci and c'i are considered distinct if the sequences of cells do not match in at least one position, that is there is such j in range from 1 to k, such that cj \neq c'j.

Input Format(From the terminal/stdin)

The first two lines contain the state of the field for the puzzle. Each of these non-empty lines contains exactly n small English letters.

The next line is left empty.

The next line is non-empty and contains word w, consisting of small English letters.

The length of each line doesn't exceed 2000.

Output Format(To the terminal/stdout)

Print a single integer - the number of distinct solutions for the puzzle modulo 109+7.

Sample Input 1

Copy
code
edoc code
    \n
    ·    \n

Sample Output 1

Copy
4
 \n

Sample Input 2

Copy
aaa
aaa aa
   \n
   ·  \n

Sample Output 2

Copy
14
  \n

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