#include <bits/stdc++.h>
using namespace std;
void err(istream_iterator<string> it) {}
template <typename T, typename... Args>
void err(istream_iterator<string> it, T a, Args... args) {
  cerr << *it << " = " << a << '\n';
  err(++it, args...);
}
template <class T1, class T2>
ostream &operator<<(ostream &os, const pair<T1, T2> &a) {
  return os << '(' << a.first << ", " << a.second << ')';
}
template <class T>
ostream &operator<<(ostream &os, const vector<T> &a) {
  os << '[';
  for (unsigned long long i = 0; i < a.size(); i++)
    os << a[i] << (i < a.size() - 1 ? ", " : "");
  os << ']';
  return os;
}
template <class T>
ostream &operator<<(ostream &os, const set<T> &a) {
  os << '{';
  for (typename set<T>::iterator it = a.begin(); it != a.end(); it++) {
    typename set<T>::iterator jt = it;
    os << *it << (++jt != a.end() ? ", " : "");
  }
  os << '}';
  return os;
}
template <class T1, class T2>
ostream &operator<<(ostream &os, map<T1, T2> &a) {
  os << "{\n";
  for (typename map<T1, T2>::iterator it = a.begin(); it != a.end(); it++) {
    typename map<T1, T2>::iterator jt = it;
    os << "  " << it->first << ": " << it->second
       << (++jt != a.end() ? ",\n" : "\n");
  }
  os << '}';
  return os;
}
long long n, m;
long long a[2005];
long long dp[2005][2];
bool check(long long lim) {
  memset(dp, 127, sizeof(dp));
  dp[0][0] = dp[0][1] = 0;
  for (long long i = 1; i <= n; i++) {
    dp[i][0] = min(dp[i - 1][0], dp[i - 1][1]) + 1;
    dp[i][1] = min(dp[i][1], i - 1);
    for (long long j = 1; j < i; j++) {
      long long diff = abs(a[i] - a[j]);
      if (diff > lim * (i - j)) continue;
      dp[i][1] = min(dp[i][1], dp[j][1] + (i - j - 1));
    }
  }
  if (min(dp[n][0], dp[n][1]) <= m) return true;
  return false;
}
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cin >> n >> m;
  for (long long i = 1; i <= n; i++) cin >> a[i];
  long long l = 0, r = 2e9;
  while (l != r) {
    long long mid = (l + r) / 2;
    if (check(mid))
      r = mid;
    else
      l = mid + 1;
  }
  cout << l << '\n';
}
