### Problem Statement

You are given a int[] A. An integer K is irreducible with respect to A if K cannot be represented as a sum of one or more elements from A, where each element of A may be used at most once. Return the smallest positive integer that is irreducible with respect to A.

### Definition

 Class: IrreducibleNumber Method: getIrreducible Parameters: int[] Returns: int Method signature: int getIrreducible(int[] A) (be sure your method is public)

### Constraints

-A will contain between 1 and 3 elements, inclusive.
-Each element of A will be between 1 and 100, inclusive.

### Examples

0)

 `{1,1}`
`Returns: 3`
 1 can be expressed as 1, and 2 can be expressed as 1+1.
1)

 `{1,2}`
`Returns: 4`
2)

 `{1,3}`
`Returns: 2`
3)

 `{4, 1, 3}`
`Returns: 2`

#### Problem url:

http://www.topcoder.com/stat?c=problem_statement&pm=6813

#### Problem stats url:

http://www.topcoder.com/tc?module=ProblemDetail&rd=10003&pm=6813

Pawa

#### Testers:

PabloGilberto , brett1479 , Olexiy , lovro

#### Problem categories:

Simple Search, Iteration