Codeforces 327C 乘法逆元 + 费马小定理 || 等比数列二分求和取模

C. Magic Five
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

There is a long plate s containingn digits. Iahub wants to delete some digits (possibly none, but he is not allowed to delete all the digits) to form his "magic number" on the plate, a number that is divisible by5. Note that, the resulting number may contain leading zeros.

Now Iahub wants to count the number of ways he can obtain magic number, modulo1000000007 (109 + 7). Two ways are different, if the set of deleted positions ins differs.

Look at the input part of the statement, s is given in a special form.

Input

In the first line you're given a string a (1 ≤ |a| ≤ 105), containing digits only. In the second line you're given an integerk (1 ≤ k ≤ 109). The plates is formed by concatenating k copies of a together. That isn = |ak.

Output

Print a single integer — the required number of ways modulo1000000007 (109 + 7).

Examples
Input
1256
1
Output

     
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