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

def calc(x):
    count = 0
    for a in A:
        if a >= x*m:
            count += a-x*m
        else:
            count -= x*m-a
        if count < 0:
            return 0

    return 1
l = 0
r = 10**10
while r > l + 1:
    c = (r+l)//2

    if calc(c):
        l = c
    else:
        r = c

print(l)