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

def ok(s):
    tame = 0
    res = True
    for i in range(n):
        if a[i] < s:
            if tame + a[i] < s:
                res = False
                break
            else:
                tame -= s-a[i]
        else:
            tame += a[i] - s
    return res
l = -1
r = 10 ** 9 + 1
while r-l>1:
    mid = (l + r) // 2
    if ok(mid):
        l = mid
    else:
        r = mid
print(l//m)