/*
Coded by thegamercoder19
GL
*/
#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
#define M_PI 3.14159265358979323846
#define FILER 0
using ll = long long;
using ull = unsigned long long;
using ld = long double;
const ll MOD = pow(10, 9) + 7;
const ll INFL = 0x3f3f3f3f3f3f3f3f;
const ull INFUL = 0x3f3f3f3f3f3f3f3f;
const ll INFT = 0x3f3f3f3f;
const ull MAX = 1LL << 24;
const ll MODD = 998244353;
const double EPS = 1e-10;
#define V vector
#define pll pair<ll, ll>
#define pull2 pair<ull,ull>
#define MS multiset
#define M map
#define Q queue
#define PQ priority_queue
#define IOF ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define FOR(typ,i,a,b,c) for(typ i = a; i < b; i += c)
#define FORR(typ,i,a,b,c) for(typ i = a; i > b; i -= c)
#define FORA(a,i) for(auto &i : a)
#define all(v) v.begin(),v.end()
#define sz(v) v.size()
#define sorta(a) sort(all(a))
#define sortd(a) sort(all(a), greater<ll>())
#define setp(x) setprecision(x)<<fixed
#define RET return
#define log(a,b) log(b)/log(a)
#define WH(s) while(s)
#define WHI(t) WH(t--)
#define YES cout<<"YES"<<endl;
#define NO cout<<"NO"<<endl;
#define Yes cout<<"Yes"<<endl;
#define No cout<<"No"<<endl;
#define YESNO(s) cout << (s ? "YES" : "NO") << endl;
#define YesNo(s) cout<<(s?"Yes":"No")<<endl;
#define TYP 0
using namespace std;
ll n, k;
V<ll> a;
V<V<ll>> dp;
void solve()
{
cin >> n >> k;
dp.resize(n + 1, V<ll>(k + 1, INFL));
a.resize(n + 1);
FOR(ll, i, 1, n + 1, 1)cin >> a[i];
dp[0][0] = 0;
dp[1][1] = 1;
FOR(ll, i, 2, n + 1, 1)dp[i][1] = dp[i - 1][1] + a[i] - a[i - 1];
FOR(ll, i, 1, n + 1, 1)
FOR(ll, j, 2, k + 1, 1)
dp[i][j] = min(dp[i - 1][j] + a[i] - a[i - 1], dp[i - 1][j - 1] + 1);
cout << dp[n][k] << endl;
}
void init()
{
if (FILER)
{
freopen("pump.in", "r", stdin);
freopen("pump.out", "w", stdout);
}
}
void handle()
{
init();
ll t = 1;
if (TYP)cin >> t;
WHI(t)solve();
}
int main()
{
IOF
handle();
RET 0;
}
