#include <iostream>
#include <vector>
#include <algorithm>
#define int long long
using namespace std;
signed main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
int oriN, k; cin >> oriN >> k;
vector<int> vals;
int cur = 0;
for (int i = 0; i < oriN; ++i) {
int temp; cin >> temp;
if (cur == 0 || ((temp < 0) && (cur < 0)) || (temp > 0) && (cur > 0)) cur += temp;
else {
vals.push_back(cur);
cur = temp;
}
}
if (cur) vals.push_back(cur);
int newN = vals.size();
static int dp[2005][2005][2] {0};
for (int i = 1; i <= newN; ++i) {
for (int j = 1; j <= k; ++j) {
dp[i][j][1] = max(dp[i - 1][k][1], dp[i - 1][k - 1][0]) + vals[i - 1];
dp[i][j][0] = max(dp[i - 1][k][1], dp[i - 1][k][0]);
}
}
cout << max(dp[newN][k][1], dp[newN][k][0]) << '\n';
return 0;
}
