#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int, int>
#define pll pair<ll, ll>
#define ff first
#define ss second
#define pb push_back
#define SZ(x) ((int)(x).size())
#define all(x) x.begin(), x.end()
#define debug(x) cout << #x << ": " << x << " "
#define nl cout << "\n"
#define rep(i, a, b) for(int i = (a); i < (b); i++)
#define per(i, a, b) for(int i = (a); i >= (b); i--)
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const ll INF = 1e16;
const int MAXN = 3e5+100;
int N, K, a[MAXN];
ll dp[MAXN];
pll get(ll penalty){
vector<ll> dp(N + 1, 0), cnt(N + 1, 0);
ll s = 0, curcnt = 0, mx = 0, mxcnt = 0;
rep(i, 1, N + 1){
dp[i] = dp[i - 1], cnt[i] = cnt[i - 1];
s += a[i];
if(s < 0){
s = 0, curcnt = 0;
}
if(mx < s){
mx = s, mxcnt = curcnt;
}
if(mx - penalty > dp[i]){
dp[i] = mx - penalty;
cnt[i] = mxcnt + 1;
}
if(dp[i] > s){
s = dp[i], curcnt = cnt[i];
}
if(s > mx){
mx = s, mxcnt = cnt[i];
}
}
return {dp[N], cnt[N]};
}
void solve(){
cin >> N >> K;
int cnt = 0;
rep(i, 1, N + 1){
cin >> a[i];
}
ll l = -1, r = INF;
while(r - l > 1){
ll m = (l + r) / 2;
pll ans = get(m);
if(ans.ss <= K){
r = m;
} else{
l = m;
}
}
pll ans = get(r);
ll solution = ans.ff + ans.ss * r;
cout << solution;
}
int main(){
ios_base::sync_with_stdio(false), cin.tie(nullptr);
solve();
return 0;
}
