import itertools
from copy import deepcopy
from functools import cache
import sys
sys.setrecursionlimit(10 ** 9)
import math
from collections import Counter, deque
input = lambda: sys.stdin.readline().rstrip()
mod = 998244353

n, k = map(int, input().split())
a = list(map(int, input().split()))

now_dp = [[-math.inf, -math.inf] for _ in range(k + 1)]
now_dp[0][1] = 0

# print(dp)

for i in range(n):
    next_dp = deepcopy(now_dp)
    for j in range(k + 1):
        if j == 0:
            continue
        else:
            if now_dp[j][0] != -math.inf:
                next_dp[j][1] = max(now_dp[j][1], now_dp[j][0])

            if now_dp[j - 1][1] != -math.inf:
                next_dp[j][0] = now_dp[j - 1][1] + a[i]
    now_dp = next_dp
# print(next_dp)

if max(next_dp[-1]) == -math.inf:
    print("Impossible")
else:
    print(max(next_dp[-1]))