import sys
sys.setrecursionlimit(10**7)

def f(v):
    if v < A[0]:
        return v
    val = 0
    for i in range(N):
        if v < A[i]:
            break
        val = max(val, f(v%A[i]))
    return val

N, K = map(int, input().split())
A = list(map(int, input().split()))
A.sort()
print(f(K))