#include <bits/stdc++.h>
//#include <atcoder/all>
using namespace std;
// using namespace atcoder;
// using mint = modint1000000007;
// const int mod = 1000000007;
// using mint = modint998244353;
// const int mod = 998244353;
// const int INF = 1e9;
const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i, l, r) for (int i = (l); i < (r); ++i)
#define rrep(i, n) for (int i = (n)-1; i >= 0; --i)
#define rrep2(i, l, r) for (int i = (r)-1; i >= (l); --i)
#define all(x) (x).begin(), (x).end()
#define allR(x) (x).rbegin(), (x).rend()
#define P pair<int, int>
template<typename A, typename B> inline bool chmax(A& a, const B& b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A& a, const B& b) { if (a > b) { a = b; return true; } return false; }

int main() {
	std::ios::sync_with_stdio(false);
	std::cin.tie(nullptr);
	int n, k; cin >> n >> k;
	vector<int>a(n);
	rep(i, n)cin >> a[i];
	vector dp(k + 1, vector<long long>(2, -LINF));
	dp[0][0] = 0;
	rep(i, n) {
		vector ndp(k + 1, vector<long long>(2, -LINF));
		rep(x, k + 1)rep(y, 2) {
			if (dp[x][y] == -LINF)continue;
			if (x != k && y == 0) {// kill
				chmax(ndp[x + 1][1], dp[x][y] + a[i]);
			}
			{// nokill
				chmax(ndp[x][0], dp[x][y]);
			}
		}
		ndp.swap(dp);
	}
	auto ans = max(dp[k][0], dp[k][1]);
	if (ans == -LINF)cout << "Impossible" << endl;
	else cout << ans << endl;
	return 0;
}