n, k = map(int, input().split())
a = list(map(int, input().split()))
dp = [[[-10**18] * 2 for _ in range(k + 1)] for __ in range(n)]
for i in range(n):
    dp[i][0][0] = 0
dp[0][1][1] = a[0]
for i in range(1, k + 1):
    for j in range(1, n):
        dp[j][i][1] = dp[j - 1][i - 1][0] + a[j]
        dp[j][i][0] = max(dp[j - 1][i][0], dp[j - 1][i][1])
if max(dp[-1][-1][0], dp[-1][-1][1]) <= -10**16:
    print("Impossible")
else:
    print(max(dp[-1][-1][0], dp[-1][-1][1]))