#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int N, K;
    cin >> N >> K;
    vector dp(N + 1, vector(K + 1, vector<ll>(2, LLONG_MIN)));
    dp[0][0][0] = 0;
    auto chmax = [&](ll& a, ll b) { a = max(a, b); };
    for(int i=0; i<N; i++) {
        ll A; cin >> A;
        for(int k=0; k<K; k++) for(int f=0; f<=1; f++) {
            if(dp[i][k][f] == LLONG_MIN) continue;
            chmax(dp[i+1][k][0], dp[i][k][f]);
            if(!f) chmax(dp[i+1][k+1][1-f], dp[i][k][f] + A);
        }
    }
    ll ans = max(dp[N][K][0], dp[N][K][1]);
    if(ans == LLONG_MIN) cout << "Impossible" << endl;
    else cout << ans << endl;
}