Codeforces Round 341 (Div. 2)
E
Wet Shark and Blocks
Codeforces
2000
原题
← D→
翻译中…

There are $*b*$ blocks of digits. Each one consisting of the same $*n*$ digits, which are given to you in the input. Wet Shark must choose exactly one digit from each block and concatenate all of those digits together to form one large integer. For example, if he chooses digit $1$ from the first block and digit $2$ from the second block, he gets the integer $12$.

翻译中…

Wet Shark then takes this number modulo $*x*$. Please, tell him how many ways he can choose one digit from each block so that he gets exactly $*k*$ as the final result. As this number may be too large, print it modulo $10^{9} + 7$.

翻译中…

Note, that the number of ways to choose some digit in the block is equal to the number of it's occurrences. For example, there are $3$ ways to choose digit $5$ from block 3 5 6 7 8 9 5 1 1 1 1 5.

翻译中…

Input

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The first line of the input contains four space-separated integers, $*n*$, $*b*$, $*k*$ and $*x*$ ($2 ≤ *n* ≤ 50 000, 1 ≤ *b* ≤ 10^{9}, 0 ≤ *k* < *x* ≤ 100, *x* ≥ 2$) — the number of digits in one block, the number of blocks, interesting remainder modulo $*x*$ and modulo $*x*$ itself.

翻译中…

The next line contains $*n*$ space separated integers $*a*_{*i*}$ ($1 ≤ *a*_{*i*} ≤ 9$), that give the digits contained in each block.

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Output

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Print the number of ways to pick exactly one digit from each blocks, such that the resulting integer equals $*k*$ modulo $*x*$.

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Note

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In the second sample possible integers are $22$, $26$, $62$ and $66$. None of them gives the remainder $1$ modulo $2$.

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In the third sample integers $11$, $13$, $21$, $23$, $31$ and $33$ have remainder $1$ modulo $2$. There is exactly one way to obtain each of these integers, so the total answer is $6$.

翻译中…

样例

Input #1
12 1 5 10
3 5 6 7 8 9 5 1 1 1 1 5
Output #1
3
InputCopy OutputCopy
Input #2
3 2 1 2
6 2 2
Output #2
0
InputCopy OutputCopy
Input #3
3 2 1 2
3 1 2
Output #3
6
InputCopy OutputCopy
题目信息
题号
621E
时间限制
2 s
内存限制
256 MB
标签
动态规划
矩阵

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