N,K=map(int,input().split())
A=list(map(int,input().split()))
dp=[[-10**15]*(2*(K+1)) for i in range(N+1)]
dp[0][0]=0
for i in range(N):
  for j in range(K+1):
    dp[i+1][2*j]=max(dp[i][2*j],dp[i][2*j+1])
    if j<K:
      dp[i+1][2*(j+1)+1]=dp[i][2*j]+A[i]
result=max(dp[N][2*K],dp[N][2*K+1])
if result<-10**11:
  print('Impossible')
  exit()
print(result)