#include<bits/stdc++.h>
using namespace std;
int main(){
    cin.tie(nullptr)->ios::sync_with_stdio(false);
    int N,K;
    cin>>N>>K;
    vector<long long> A(N);
    for(int i=0;i<N;i++) cin>>A[i];
    const long long INF=1ll<<60;
    vector dp(2,vector<long long>(K+1,-INF));
    dp[0][0]=0;
    for(int i=0;i<N;i++){
        vector ndp(2,vector<long long>(K+1,-INF));
        for(int j=0;j<2;j++) for(int k=0;k<=K;k++){
            ndp[0][k]=max(ndp[0][k],dp[j][k]);
            if(!j and k!=K){
                ndp[1][k+1]=max(ndp[1][k+1],dp[0][k]+A[i]);
            }
        }
        swap(dp,ndp);
    }
    const long long ans=max(dp[0][K],dp[1][K]);
    if(ans<=-10000000000000000) cout<<"Impossible\n";
    else cout<<ans<<"\n";
}