COEF - Coeficientes


The problem is to calculate the coefficients in expansion of polynomial (x1+x2+...+xk)n.

Input

The input will consist of a set of pairs of lines. The first line of the pair consists of two integers n and k separated with space (0 < n, k <13). This integers define the power of the polynomial and the amount of the variables. The second line in each pair consists of k non-negative integers n1, ..., nk, where n1+...+nk=n.

Output

For each input pair of lines the output line should consist one integer, the coefficient by the monomial x1n1x2n2...xknk in expansion of the polynomial (x1+x2+...+xk)n.

Example

Input:
2 2
1 1
2 12
1 0 0 0 0 0 0 0 0 0 1 0

Output:
2
2

hide comments
abhi: 2013-08-23 16:28:42

getting WA give some more input...

Shubham Gupta: 2013-06-25 04:43:27

Thank u NAMANDEEP :)

Vaibhav Agarwal: 2013-06-15 18:06:18

Easy one..... with this i complete 100 problems on spoj :)

Ouditchya Sinha: 2013-05-26 16:43:51

Piece of cake.. :)

Yashpal: 2013-03-27 08:23:05

getting WA....
edit(francky) : Please use the forum for that. Read the notes below.

Last edit: 2013-03-27 09:31:28
Venkatesh Ganesan: 2012-11-18 17:05:06

what's the input termination condition? no limit given
@namandeep What u said is giving errors

RANA: 2012-06-30 12:15:43

easy one.... :)

sachin tendulkar: 2012-05-26 19:41:40

THANX NAMANDEEP

(Tjandra Satria Gunawan)(曾毅昆): 2012-05-02 14:00:06

easy... :)


Added by:Coach UTN FRSF
Date:2010-06-02
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: NODEJS OBJC PERL6 SQLITE VB.NET
Resource:http://uva.onlinejudge.org/external/101/10105.html