N, K = map(int, input().split())
A = list(map(int, input().split()))

dp = [[[-10**18]*(K+1) for i in range(2)] for j in range(N+1)]

dp[0][0][0] = 0

for i in range(N):
    for j in range(2):
        for k in range(K+1):
            if dp[i][j][k] == -10**18:
                continue
            dp[i+1][0][k] = max(dp[i+1][0][k], dp[i][j][k]) # とらない
            if k < K and j==0:
                dp[i+1][1][k+1] = max(dp[i+1][1][k+1], dp[i][0][k]+A[i]) # とる
ans = -10**18
if dp[N][0][K] == dp[N][1][K] == -10**18:
    print("Impossible")
else:
    ans = max(dp[N][0][K], dp[N][1][K])
    print(ans)