Stamps Problem

Problem Background

Special for beginners, ^_^

Problem Description

There are $m$ kinds of stamps with known denominations, and $n$ stamps of each kind. Using no more than $n$ stamps in total, from denomination 1 onward, what is the largest contiguous range of denominations you can form? ($1 \le m \le 100$, $1 \le n \le 100$, $1 \le$ stamp denomination $\le 255$).

Input Format

The first line: the values of $m,n$, separated by a single space.

The second line: $A[1\dots m]$ (the denominations), separated by single spaces.

Output Format

The maximum value of the contiguous range of denominations.

Sample Input

3 4
1 2 4

Sample Output

14

Constraints

1s, 1024KiB for each test case.