import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Iterator;


public class Main_yukicoder324_1 {

	public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        Printer pr = new Printer(System.out);

        final int INF = Integer.MAX_VALUE / 2;

        int n = sc.nextInt();
        int m = sc.nextInt();
        int[] w = new int[n];
        for (int i = 0; i < n; i++) {
        	w[i] = sc.nextInt();
        }

        if (m == 0) {
        	pr.println(0);

        	pr.close();
        	sc.close();
        	return;
        }

        int[][][] dp = new int[2][m + 1][2];
        int[][][] dp2 = new int[2][m + 1][2];
        for (int i = 0; i < 2; i++) {
        	for (int j = 0; j <= m; j++) {
        		Arrays.fill(dp[i][j], -INF);
        		Arrays.fill(dp2[i][j], -INF);
        	}
        }
        for (int i = 0; i < 2; i++) {
        	dp[i][0][0] = 0;
        }
        dp2[0][1][1] = 0;

        for (int i = 1; i < n; i++) {
        	int tmpi = i % 2;
        	int tmpim = (i + 1) % 2;
        	for (int j = 1; j <= m; j++) {
        		if (i != n - 1) {
        			dp[tmpi][j][0] = Math.max(dp[tmpim][j][0], dp[tmpim][j][1]);
        			dp[tmpi][j][1] = Math.max(dp[tmpim][j - 1][0], dp[tmpim][j - 1][1] + w[i - 1]);
        			dp2[tmpi][j][0] = Math.max(dp2[tmpim][j][0], dp2[tmpim][j][1]);
        			dp2[tmpi][j][1] = Math.max(dp2[tmpim][j - 1][0], dp2[tmpim][j - 1][1] + w[i - 1]);
        		} else {
        			dp[tmpi][j][0] = Math.max(dp[tmpim][j][0], dp[tmpim][j][1]);
        			dp[tmpi][j][1] = Math.max(dp[tmpim][j - 1][0], dp[tmpim][j - 1][1] + w[i - 1]);
        			dp2[tmpi][j][0] = Math.max(dp2[tmpim][j][0], dp2[tmpim][j][1]);
        			dp2[tmpi][j][1] = Math.max(dp2[tmpim][j - 1][0] + w[i], dp2[tmpim][j - 1][1] + w[i - 1] + w[i]);
        		}
        	}
        }

        int max = -INF;
        for (int i = 0; i < 2; i++) {
        	max = Math.max(max, dp[(n - 1) % 2][m][i]);
        	max = Math.max(max, dp2[(n - 1) % 2][m][i]);
        }

        pr.println(max);

        pr.close();
        sc.close();
    }

    @SuppressWarnings("unused")
	private static class Scanner {
		BufferedReader br;
		Iterator<String> it;

		Scanner (InputStream in) {
			br = new BufferedReader(new InputStreamReader(in));
		}

		String next() throws RuntimeException  {
			try {
				if (it == null || !it.hasNext()) {
					it = Arrays.asList(br.readLine().split(" ")).iterator();
				}
				return it.next();
			} catch (IOException e) {
				throw new IllegalStateException();
			}
		}

		int nextInt() throws RuntimeException {
			return Integer.parseInt(next());
		}

		long nextLong() throws RuntimeException {
			return Long.parseLong(next());
		}

		float nextFloat() throws RuntimeException {
			return Float.parseFloat(next());
		}

		double nextDouble() throws RuntimeException {
			return Double.parseDouble(next());
		}

		void close() {
			try {
				br.close();
			} catch (IOException e) {
//				throw new IllegalStateException();
			}
		}
	}

	private static class Printer extends PrintWriter {
		Printer(PrintStream out) {
			super(out);
		}
	}
}