import math
import sys

sys.setrecursionlimit(10 ** 6)
from typing import List, Tuple

int1 = lambda x: int(x) - 1
input = lambda: sys.stdin.readline().rstrip('\n')
ii = lambda: int(input())
vi = lambda: list(map(int, input().split()))
vi1 = lambda: list(map(int1, input().split()))


def dbg(*args, **kwargs):
    print(*(repr(arg) for arg in args), *(f'{k}: {repr(v)}' for k, v in kwargs.items()),
          sep='; ', file=sys.stderr, flush=True)


def main():
    n, k = vi()
    a = vi()

    d = [-math.inf]*(k+1)
    e = [-math.inf]*(k+1)
    d[0] = 0
    for i in a:
        ne = [-math.inf] + [i + v for v in d[:-1]]
        d = [max(a, b) for a, b in zip(d, e)]
        e = ne

    ans = max(e[-1], d[-1])

    if math.isinf(ans):
        return 'Impossible'
    else:
        return ans




def _start():
    if (ret := main()) is not None:
        print(*ret) if isinstance(ret, List) or isinstance(ret, Tuple) else print(ret)


if __name__ == '__main__':
    _start()