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#include <bits/stdc++.h>

using namespace std;

typedef long long int LL;

const int N = 207;
const int M = 61;

const LL MX = 1000LL * 1000 * 1000;
const LL INF = 2LL * MX * MX;

int n;
LL in[N];
LL pref[N];
LL dp[M][N][N][2];

LL m;
bool bit[M];

int main(){
	scanf("%d %lld", &n, &m);
	for(int i = 1; i <= n; ++i)
		scanf("%lld", &in[i]),
		pref[i] = pref[i - 1] + in[i];
	
	for(int i = M - 2; i >= 0; --i)
		if(m & (1LL << i))
			bit[i + 1] = true;
	
	for(int i = 1; i <= n; ++i)
		for(int j = i + 1; j <= n; ++j)
			dp[0][i][j][0] = dp[0][i][j][1] = -INF;
	
	for(int t = 1; t < M; ++t){
		for(int i = 1; i <= n; ++i)
			for(int j = i; j <= n; ++j){
				{
					dp[t][i][j][0] = -INF;
					for(int k = i - 1; k <= j; ++k)
						dp[t][i][j][0] = max(dp[t][i][j][0], dp[t - 1][i][k][0] + dp[t - 1][k + 1][j][0] + pref[j] - pref[k]);
				}
				
				{
					dp[t][i][j][1] = dp[t - 1][i][j][1];
					if(bit[t])
						for(int k = i - 1; k <= j; ++k)
							dp[t][i][j][1] = max(dp[t][i][j][1], dp[t - 1][i][k][0] + dp[t - 1][k + 1][j][1] + pref[j] - pref[k]);
				}
				
//				printf("dp[%d][%d][%d][0] = %lld\n", t, i, j, dp[t][i][j][0]);
//				printf("dp[%d][%d][%d][1] = %lld\n", t, i, j, dp[t][i][j][1]);
			}
	}

	printf("%lld\n", dp[M - 1][1][n][1]);
	return 0;
}