#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<complex>
#include<bitset>
#include<stack>
#include<unordered_map>
#include<utility>
#include<tuple>
using namespace std;
typedef long long ll;
typedef unsigned int ui;
const ll mod = 1000000007;
const ll INF = (ll)1000000007 * 1000000007;
typedef pair<int, int> P;
#define stop char nyaa;cin>>nyaa;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define Per(i,sta,n) for(int i=n-1;i>=sta;i--)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
typedef long double ld;
const ld eps = 1e-8;
const ld pi = acos(-1.0);
typedef pair<ll, ll> LP;
int dx[4]={1,-1,0,0};
int dy[4]={0,0,1,-1};


int n,m,k;
ll a[3010],S[3010];
ll dp[3010][3010];
deque<int> que1[3010],que2[3010];

void solve(){
  cin >> n >> k >> m;
  rep(i,n+1){
    rep(j,k){
      dp[j][i]=-INF;
    }
  }
  rep(i,n){
    cin >> a[i];
  }
  rep(i,n){
    S[i+1]=S[i]+a[i];
  }
  dp[0][0]=0;
  rep(i,k){
    que1[i].push_back(0);
    que2[i].push_back(0);
  }
  Rep(i,1,n+1){
    Rep(j,1,k){
      if(que1[j-1][0]==i-m-1) que1[j-1].pop_front();
      if(que2[j-1][0]==i-m-1) que2[j-1].pop_front();
      ll res1=dp[j-1][que1[j-1][0]];
      ll res2=dp[j-1][que2[j-1][0]];
      //cout << res1 << " " << res2 << endl;
      //cout << que1[j].back() << endl;
      dp[j][i]=max(res1+S[i],res2-S[i]);
      while(dp[j][que1[j].back()]-S[que1[j].back()]<=dp[j][i]-S[i]){
        que1[j].pop_back();
        if(que1[j].empty()) break;
      }
      que1[j].push_back(i);
      while(dp[j][que2[j].back()]+S[que2[j].back()]<=dp[j][i]+S[i]){
        que2[j].pop_back();
        if(que2[j].empty()) break;
      }
      que2[j].push_back(i);
      //cout << i << " " << j << " " << dp[j][i] << endl;
    }
  }
  ll ans=0;
  Rep(i,n-m,n){
    ans=max(ans,dp[k-1][i]+abs(S[n]-S[i]));
  }
  cout << ans << endl;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << fixed << setprecision(50);
    solve();
}