import std.conv, std.functional, std.range, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.bitmanip, std.complex, std.container, std.math, std.mathspecial, std.numeric, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }


// T: monoid
// op: T * T -> T
// query(a, b): returns t_a ... t_{b-1}
class SegmentTree(T, alias op) {
  import std.functional : binaryFun;
  alias opFun = binaryFun!op;
  const(T) idT;

  int n;
  T[] ts;
  this(int n_, const(T) idT) {
    this.idT = idT;
    for (n = 1; n < n_; n <<= 1) {}
    ts = new T[n << 1];
    ts[] = idT;
  }
  this(inout(T)[] ts_, const(T) idT) {
    this.idT = idT;
    const n_ = cast(int)(ts_.length);
    for (n = 1; n < n_; n <<= 1) {}
    ts = new T[n << 1];
    ts[0 .. n] = idT;
    ts[n .. n + n_] = ts_[];
    ts[n + n_ .. n << 1] = idT;
    build();
  }
  ref T at(int a) {
    return ts[n + a];
  }
  void build() {
    foreach_reverse (a; 1 .. n) ts[a] = opFun(ts[a << 1], ts[a << 1 | 1]);
  }
  void set(int a, const(T) val) {
    ts[a += n] = val;
    for (; a >>= 1; ) ts[a] = opFun(ts[a << 1], ts[a << 1 | 1]);
  }
  void mulL(int a, const(T) val) {
    set(a, opFun(val, ts[a + n]));
  }
  void mulR(int a, const(T) val) {
    set(a, opFun(ts[a + n], val));
  }
  T query(int a, int b) const {
    T prodL = idT, prodR = idT;
    for (a += n, b += n; a < b; a >>= 1, b >>= 1) {
      if (a & 1) prodL = opFun(prodL, ts[a++]);
      if (b & 1) prodR = opFun(ts[--b], prodR);
    }
    return opFun(prodL, prodR);
  }
}


enum INF = 10L^^18;

void main() {
  try {
    for (; ; ) {
      const N = readInt();
      const K = readInt();
      const M = readInt();
      auto A = new long[N];
      foreach (i; 0 .. N) {
        A[i] = readLong();
      }
      
      auto ASum = new long[N + 1];
      foreach (i; 0 .. N) {
        ASum[i + 1] = ASum[i] + A[i];
      }
      
      auto ps = new Tuple!(long, int)[N + 1];
      foreach (i; 0 .. N + 1) {
        ps[i] = tuple(ASum[i], i);
      }
      ps.sort;
      auto qs = new int[N + 1];
      foreach (j; 0 .. N + 1) {
        qs[ps[j][1]] = j;
      }
      
      auto crt = new long[N + 1];
      crt[] = -INF;
      crt[0] = 0;
      foreach (k; 0 .. K) {
        auto nxt = new long[N + 1];
        auto seg0 = new SegmentTree!(long, max)(N + 1, -INF);
        auto seg1 = new SegmentTree!(long, max)(N + 1, -INF);
        foreach (i; k + 1 .. N + 1) {
          // push i - 1
          seg0.set(qs[i - 1], crt[i - 1] - ASum[i - 1]);
          seg1.set(qs[i - 1], crt[i - 1] + ASum[i - 1]);
          // get
          chmax(nxt[i], seg0.query(0, qs[i]) + ASum[i]);
          chmax(nxt[i], seg1.query(qs[i] + 1, N + 1) - ASum[i]);
          // pop i - M
          if (i - M >= 0) {
            seg0.set(qs[i - M], -INF);
            seg1.set(qs[i - M], -INF);
          }
        }
        crt = nxt;
      }
      writeln(crt[N]);
    }
  } catch (EOFException e) {
  }
}