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
vineetpratik: 2016-06-22 07:35:42

multinomial coefficient and proper EOF.

azam_9: 2016-05-28 19:54:34

just take care input format..i.e EOF to terminate the input in C...rest piece of cake.

Last edit: 2016-05-28 19:54:48
raghav12345: 2015-11-01 09:12:38

my 50th!!!

aishik_pyne: 2015-09-19 08:51:12

what are the number of inputs?

Mayank Garg: 2015-04-04 11:26:59

my 50th !!
a piece of cake

ashish kumar: 2015-01-16 15:53:31

my 90th

#include: 2015-01-10 13:38:45

my 100th on spoj

Sahil Dua: 2014-11-08 06:47:07

Simple one. Keep trying, until you get AC in 0.00

jinkies: 2014-10-15 12:51:18

very easy, just terminate input properly

Jackson: 2014-10-10 07:16:42

Easy one...... Read Multinomial coefficients in Multinomial theorem..


Added by:Coach UTN FRSF
Date:2010-06-02
Time limit:0.333s-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