n,k = map(int,input().split())
a = list(map(int,input().split()))
ok,ng = 0,10**9+1
while ng-ok>1:
	m = (ok+ng)//2
	p = 0
	for i in range(n):
		if a[i]+p<k*m:
			ng = m
			break
		p -= k*m-a[i]
	else:
		ok = m
print(ok)