// Starcraft 2 enjoyer //
#include <bits/stdc++.h>
// #pragma GCC target("avx2")
// #pragma GCC optimize("O3")
// #pragma GCC optimize("unroll-loops")
using namespace std;
#define LSOne(X) ((X) & -(X))
const int N = 3e5 + 5;
const int M = 2e5 + 5;
const int LG = 20;
const int INF = 1e9 + 5;
const int K = 2;
const int C = 26;
const int B = 1000;
const int MOD = 998244353;
int n, k, a[N];
pair<long long, long long> dp1[2], dp2[2];
pair<long long, long long> cal(long long lmd)
{
dp1[0] = {0, 0};
dp1[1] = {-1e18, -1e18};
for (int x = 1; x <= n; x++)
{
dp2[0] = max(dp1[0], dp1[1]);
dp2[1] = max(pair<long long, long long>{dp1[0].first - lmd + a[x], dp1[0].second + 1}, {dp1[1].first + a[x], dp1[1].second});
dp1[0] = dp2[0];
dp1[1] = dp2[1];
}
// cout << lmd << "\n";
// cout << dp1[0].first << " " << dp1[0].second << "\n";
// cout << dp2[0].first << " " << dp2[0].second << "\n";
return max(dp1[0], dp1[1]);
}
inline void solve()
{
cin >> n >> k;
for (int x = 1; x <= n; x++)
{
cin >> a[x];
}
long long l = 1, r = 1e13, b = 0;
while (l <= r)
{
long long m = (l + r) / 2;
if (cal(m).second >= k)
{
l = m + 1;
b = m;
}
else
{
r = m - 1;
}
}
cout << cal(b).first + k * b;
}
signed main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int t = 1;
// cin >> t;
for (int x = 1; x <= t; x++)
{
solve();
}
return 0;
}
