#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
typedef long long ll;
using namespace __gnu_pbds;
using namespace std;
template <typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
int n, k;
cin >> n >> k;
vector<ll> T(n+1);
for(int i=1; i<=n; ++i) cin >> T[i];
ll inf = 1e15;
vector<vector<ll>> dp(n+1, vector<ll>(k+1, inf));
dp[0][0] = 0;
for(int i=1; i<=n; ++i) {
int d = T[i]-T[i-1];
for(int x=1; x<=k; ++x) {
dp[i][x] = min(dp[i-1][x] + d, dp[i-1][x-1]+1);
}
}
cout << dp[n][k] << "\n";
return 0;
}
