#include <iostream>
#include <algorithm>
using namespace std;

int arr[100010];
int dp[100010][110];

const int MAXNEG = -1000000000;

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    freopen("krasi.in", "r", stdin);
    freopen("krasi.out", "w", stdout);

    int n, k;
    cin>>n>>k;

    for(int i=0; i<n; i++){
        cin>>arr[i];
    }

    for(int i=0; i<n; i++){
        for(int j=0; j<=k; j++){
            dp[i][j] = MAXNEG;
        }
    }

    int ans = MAXNEG;

    for(int i=0; i<n; i++){
        if(arr[i] != 0) {
            dp[i][0] = arr[i];
        }
        else {
            dp[i][1] = arr[i];
        }
        ans = max(ans, arr[i]);
    }

    for(int i=1; i<n; i++){
        //dp[i][0] = max(dp[i][0], dp[i-1][0]);
        if(arr[i] != 0){
            int m = max(dp[i-1][0] + arr[i], arr[i]);
            dp[i][0] = m;
            ans = max(ans,m);
        }
        else {
            dp[i][1] = max(arr[i], dp[i-1][0]);
            ans = max(ans, dp[i][1]);
        }
        for(int j=1; j<=k; j++){
            if(arr[i] != 0){
                int m = dp[i-1][j] + arr[i];
                dp[i][j] = m;
                if(m > ans) ans = m;
            }
            else {
                int m = dp[i-1][j-1];
                dp[i][j] = m;
                if(m > ans) ans = m;
            }
        }
    }


    cout<<ans<<endl;
}


/*

13 2
2 3 0 5 0 -1 2 0 5 -2 1 0 6

*/