Codeforces Round 297 (Div. 2)
E
Anya and Cubes
Codeforces
2100
原题
← D→
翻译中…

Anya loves to fold and stick. Today she decided to do just that.

翻译中…

Anya has $*n*$ cubes lying in a line and numbered from $1$ to $*n*$ from left to right, with natural numbers written on them. She also has $*k*$ stickers with exclamation marks. We know that the number of stickers does not exceed the number of cubes.

翻译中…

Anya can stick an exclamation mark on the cube and get the factorial of the number written on the cube. For example, if a cube reads $5$, then after the sticking it reads $5!$, which equals $120$.

翻译中…

You need to help Anya count how many ways there are to choose some of the cubes and stick on some of the chosen cubes at most $*k*$ exclamation marks so that the sum of the numbers written on the chosen cubes after the sticking becomes equal to $*S*$. Anya can stick at most one exclamation mark on each cube. Can you do it?

翻译中…

Two ways are considered the same if they have the same set of chosen cubes and the same set of cubes with exclamation marks.

翻译中…

Input

翻译中…

The first line of the input contains three space-separated integers $*n*$, $*k*$ and $*S*$ ($1 ≤ *n* ≤ 25$, $0 ≤ *k* ≤ *n*$, $1 ≤ *S* ≤ 10^{16}$) — the number of cubes and the number of stickers that Anya has, and the sum that she needs to get.

翻译中…

The second line contains $*n*$ positive integers $*a*_{*i*}$ ($1 ≤ *a*_{*i*} ≤ 10^{9}$) — the numbers, written on the cubes. The cubes in the input are described in the order from left to right, starting from the first one.

翻译中…

Multiple cubes can contain the same numbers.

翻译中…

Output

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Output the number of ways to choose some number of cubes and stick exclamation marks on some of them so that the sum of the numbers became equal to the given number $*S*$.

翻译中…

Note

翻译中…

In the first sample the only way is to choose both cubes and stick an exclamation mark on each of them.

翻译中…

In the second sample the only way is to choose both cubes but don't stick an exclamation mark on any of them.

翻译中…

In the third sample it is possible to choose any of the cubes in three ways, and also we may choose to stick or not to stick the exclamation mark on it. So, the total number of ways is six.

翻译中…

样例

Input #1
2 2 30
4 3
Output #1
1
InputCopy OutputCopy
Input #2
2 2 7
4 3
Output #2
1
InputCopy OutputCopy
Input #3
3 1 1
1 1 1
Output #3
6
InputCopy OutputCopy
题目信息
题号
525E
时间限制
2 s
内存限制
256 MB
标签
二分
位运算
暴力
动态规划
数学
折半搜索

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