#define _CRT_SECURE_NO_WARNINGS
#include <string>
#include <vector>
#include <algorithm>
#include <numeric>
#include <set>
#include <map>
#include <queue>
#include <iostream>
#include <sstream>
#include <cstdio>
#include <cmath>
#include <ctime>
#include <cstring>
#include <cctype>
#include <cassert>
#include <limits>
#define rep(i,n) for(int (i)=0;(i)<(int)(n);++(i))
#define rer(i,l,u) for(int (i)=(int)(l);(i)<=(int)(u);++(i))
#define reu(i,l,u) for(int (i)=(int)(l);(i)<(int)(u);++(i))
#if defined(_MSC_VER) || __cplusplus > 199711L
#define aut(r,v) auto r = (v)
#else
#define aut(r,v) typeof(v) r = (v)
#endif
#define each(it,o) for(aut(it, (o).begin()); it != (o).end(); ++ it)
#define all(o) (o).begin(), (o).end()
#define pb(x) push_back(x)
#define mp(x,y) make_pair((x),(y))
#define mset(m,v) memset(m,v,sizeof(m))
#define INF 0x3f3f3f3f
#define INFL 0x3f3f3f3f3f3f3f3fLL
using namespace std;
typedef vector<int> vi; typedef pair<int,int> pii; typedef vector<pair<int,int> > vpii;
typedef long long ll; typedef vector<long long> vl; typedef pair<long long,long long> pll; typedef vector<pair<long long,long long> > vpll;
typedef vector<string> vs; typedef long double ld;
template<typename T, typename U> inline void amin(T &x, U y) { if(y < x) x = y; }
template<typename T, typename U> inline void amax(T &x, U y) { if(x < y) x = y; }

int main() {
	int N, V;
	scanf("%d%d", &N, &V);
	vector<int> C(N);
	rep(i, N) scanf("%d", &C[i]);
	reverse(all(C));
	vector<long long> sum(N+1);
	rep(i, N) sum[i+1] = sum[i] + C[i];
	long long base = sum[N];
	int V2 = max(0, V - N);
	int Mi = -1; long long Mcost = INFL;
	rep(i, N) {
//		cerr << i << ": " << (sum[N] - sum[i]) * 1. / (N - i) << endl;
		if(Mi == -1 || (sum[N] - sum[Mi]) * (N - i) > (sum[N] - sum[i]) * (N - Mi)) {
			Mcost = (sum[N] - sum[i]);
			Mi = i;
		}
	}
//	cerr << (sum[N] - sum[Mi]) * 1. / (N - Mi) << endl;
	const int XXX = 1111, YYY = 1111;
	int t = max(0, V2 / (N - Mi) - XXX);
	V2 -= (N - Mi) * t;
//	cerr << Mi << ", " << Mcost << ", " << t << ", " << Mcost * t << ", " << t << ", " << V2 << endl;
	base += Mcost * t;
	vector<long long> dp(V2 + YYY + 1, INFL);
	dp[0] = 0;
	rep(i, N) {
		int x = N - i; long long y = sum[N] - sum[i];
		rer(j, 0, V2 + YYY - x)
			amin(dp[j + x], dp[j] + y);
	}
//	rer(v, 0, V2 + YYY) cerr << v << ": " << dp[v] << endl;
	long long ans = INFL;
	rer(v, V2, V2 + YYY)
		amin(ans, dp[v]);
	ans += base;
	printf("%lld\n", ans);
	return 0;
}