N, M = map(int, input().split())
A = list(map(int, input().split()))
A.sort(reverse=True)
dp = [[0] * (M + 1) for _ in range(N + 1)]
for i in range(N - 1):
    for m in range(M + 1):
        dp[i + 2][m] = dp[i + 1][m]
    for m in range(M + 1):
        new_m = m + A[i] - A[i + 1]
        if new_m > M:
            continue
        if dp[i + 2][new_m] < dp[i][m] + A[i]:
            dp[i + 2][new_m] = dp[i][m] + A[i]
print(max(dp[N]))