import java.util.ArrayDeque; import java.util.Arrays; import java.util.Deque; public class Main { private static void solve() { int n = ni(); int k = ni(); int m = ni(); long[] a = nal(n); long[][] dp = new long[n + 1][k + 1]; for (long[] v : dp) Arrays.fill(v, Long.MIN_VALUE / 2); dp[0][0] = 0; long[] sum = new long[n + 1]; for (int i = 0; i < n; i++) { sum[i + 1] = sum[i] + a[i]; } Deque q1 = new ArrayDeque<>(); Deque q2 = new ArrayDeque<>(); for (int j = 1; j <= k; j++) { q1.clear(); q2.clear(); for (int i = 1; i <= n; i++) { if (n - i < k - j) break; long v1 = dp[i - 1][j - 1] - sum[i - 1]; long v2 = dp[i - 1][j - 1] + sum[i - 1]; long[] e1 = { v1, i }; long[] e2 = { v2, i }; while (q1.size() > 0 && q1.peekLast()[0] <= e1[0]) { q1.pollLast(); } while (q2.size() > 0 && q2.peekLast()[0] <= e2[0]) { q2.pollLast(); } q1.addLast(e1); q2.addLast(e2); if (q1.peekFirst()[1] == i - m) { q1.pollFirst(); } if (q2.peekFirst()[1] == i - m) { q2.pollFirst(); } dp[i][j] = Math.max(dp[i][j], q1.peekFirst()[0] + sum[i]); dp[i][j] = Math.max(dp[i][j], q2.peekFirst()[0] - sum[i]); } } System.out.println(dp[n][k]); } public static void main(String[] args) { new Thread(null, new Runnable() { @Override public void run() { long start = System.currentTimeMillis(); String debug = args.length > 0 ? args[0] : null; if (debug != null) { try { is = java.nio.file.Files.newInputStream(java.nio.file.Paths.get(debug)); } catch (Exception e) { throw new RuntimeException(e); } } reader = new java.io.BufferedReader(new java.io.InputStreamReader(is), 32768); solve(); out.flush(); tr((System.currentTimeMillis() - start) + "ms"); } }, "", 64000000).start(); } private static java.io.InputStream is = System.in; private static java.io.PrintWriter out = new java.io.PrintWriter(System.out); private static java.util.StringTokenizer tokenizer = null; private static java.io.BufferedReader reader; public static String next() { while (tokenizer == null || !tokenizer.hasMoreTokens()) { try { tokenizer = new java.util.StringTokenizer(reader.readLine()); } catch (Exception e) { throw new RuntimeException(e); } } return tokenizer.nextToken(); } private static double nd() { return Double.parseDouble(next()); } private static long nl() { return Long.parseLong(next()); } private static int[] na(int n) { int[] a = new int[n]; for (int i = 0; i < n; i++) a[i] = ni(); return a; } private static char[] ns() { return next().toCharArray(); } private static long[] nal(int n) { long[] a = new long[n]; for (int i = 0; i < n; i++) a[i] = nl(); return a; } private static int[][] ntable(int n, int m) { int[][] table = new int[n][m]; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { table[i][j] = ni(); } } return table; } private static int[][] nlist(int n, int m) { int[][] table = new int[m][n]; for (int i = 0; i < n; i++) { for (int j = 0; j < m; j++) { table[j][i] = ni(); } } return table; } private static int ni() { return Integer.parseInt(next()); } private static void tr(Object... o) { if (is != System.in) System.out.println(java.util.Arrays.deepToString(o)); } }