#include<cstdio>
#include<deque>
//abs part can be fixed...
long long a[3005];
long long sum[3005];
long long f[3005];
struct Element{
    int p;
    long long value;
    Element(int p=0,long long value=0):p(p),value(value){}
};
std::deque<Element>queue[3005][2];

long long abs(long long u){ return u>0?u:-u; }

long long max(long long a,long long b){ return a>b?a:b; }

int main(){
    //printf("%lld\n",sizeof(queue)/1000000);
    int n,m,k;
    scanf("%d%d%d",&n,&k,&m);
    sum[0] = 0;
    for(int i = 1; i <= n; i++){
        scanf("%lld",&a[i]);
        sum[i] = sum[i-1]+a[i];
    }
    queue[0][0].push_back(Element(0,0));
    queue[0][1].push_back(Element(0,0));
    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= k; j++){
            f[j] = 0;
            /*for(int last = max(0,i-m); last <= i-1; last++){
                //f[i][j] = max(f[i][j],f[last][j-1]+abs(sum[i]-sum[last]));
                //f[i][j] = max(f[i][j],f[last][j-1]+sum[i]-sum[last]);
                //f[i][j] = max(f[i][j],f[last][j-1]-sum[i]+sum[last]);
            }*/
            while(queue[j-1][0].size()!=0 && queue[j-1][0].front().p<i-m) queue[j-1][0].pop_front();
            while(queue[j-1][1].size()!=0 && queue[j-1][1].front().p<i-m) queue[j-1][1].pop_front();
            long long res0 = 0, res1 = 0;
            if(queue[j-1][0].size()!=0) res0 = queue[j-1][0].front().value+sum[i];
            if(queue[j-1][1].size()!=0) res1 = queue[j-1][1].front().value-sum[i];
            f[j] = max(res0,res1);
            //printf("f[%d][%d] = %lld\n",i,j,f[j]);
            //update
        }
        for(int j = 1; j <= k; j++){
            long long value = f[j]-sum[i];
            while(queue[j][0].size()!=0 && value>=queue[j][0].back().value) queue[j][0].pop_back();
            queue[j][0].push_back(Element(i,value));
            value = f[j]+sum[i];
            while(queue[j][1].size()!=0 && value>=queue[j][1].back().value) queue[j][1].pop_back();
            queue[j][1].push_back(Element(i,value));
        }
    }
    printf("%lld\n",f[k]);
    return 0;
}