#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
//libs
#include <iostream>
#include <algorithm>
#include <set>
#include <vector>
#include <string>
#include <map>
#include <complex>
#include <fstream>
#include <iomanip>
#include <cmath>
#include <queue>

using namespace std;
//defines
#define infll 8e18
#define ll long long
#define itn ll
#define vi vector<itn>
#define vvi vector<vi>
#define pii pair<itn,itn> 
//constants
const double eps = 1e-7;
const ll mod = 1000000007;
//end of definition


void solve()
{
	/*int n;
	cin >> n;
	vi a(n);
	multimap<ll,int> b;
	for (int i = 0; i < n; i++)
	{
		cin >> a[i];
		b.insert({ a[i], i });
	}
	ll ans = 0;
	for (int i = 0; i < n; i++)
	{
		ll nowmax = a[i];
		b.erase(a[i]);
		for (int j = i + 1; j < n; j++)
		{
			nowmax = max(nowmax, a[j]);
			if (a[j] * a[i] <= nowmax)
				ans++;
		}
	}
	
	cout << ans << endl;*/
	int n, k;
	cin >> n >> k;
	vi a(n);
	for (int i = 0; i < n; i++)
		cin >> a[i];

	vvi dp(n+2, vi(2*(k+3), infll));
	for (int i = 0; i <= min(k, n - 1);i++)
	dp[i][k + 3-i] = 0;
	int nul = k + 3;
	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < dp[i].size(); j++)
		{
			if (dp[i][j] == 0)
			{
				dp[i + 1][nul + k] = min(dp[i + 1][nul + k], dp[i][j] + a[i]);
			}
			if (j > 3)
			{
				dp[i + 1][j - 1] = min(dp[i + 1][j - 1], dp[i][j]);
			}
			else
			dp[i + 1][nul+k] = min(dp[i + 1][nul+k], dp[i][j] + a[i]);
		}
	}
	ll ans = infll;
	for (int i = k+3; i < dp[n].size(); i++)
		ans = min(ans, dp[n][i]);

	cout << ans << endl;

}

int main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
#ifdef _DEBUG
	freopen("input.txt", "r", stdin);
	//freopen("input.txt", "w", stdout);
#endif

		solve();

	return 0;
}