n, m = map(int, input().split())
a = list(map(int, input().split()))

acc = [0]
for i in a:
    acc.append(acc[-1] + i)

left = -1
right = 10**9

while abs(right - left) > 1:
    mid = (right + left) // 2
    flag = True
    for i in range(n):
        if acc[i + 1] >= (i + 1) * mid * m:
            continue
        else:
            flag = False
            break

    if flag:
        left = mid
    else:
        right = mid

print(left)