#yuki_77
import math

n=int(raw_input())
a=map(int,raw_input().split())
sa=sum(a)
nc=int(math.sqrt(sa))

r=[]
for i in xrange(1,nc+1):
 r.append(i)
for i in xrange(1,nc):
 r.append(nc-i)

if len(a)>len(r):
 for i in xrange(len(a)-len(r)):
  r.append(0)
elif len(a)<len(r):
 for i in xrange(len(r)-len(a)):
  a.append(0)

re=[]
for i in xrange(len(r)):
 re.append(a[i]-r[i])
residue=sum(re)
move=0
for i in xrange(len(re)):
 if re[i]<0:
  move+=abs(re[i])

res=move+residue
print res