N=int(input())
A=list(map(int, input().split()))
D=[0]*N
B=[]
d=0
for i in A:
  d+=i
  B.append(d)
import bisect
for i in range(N):
  d=bisect.bisect_left(B,i+1)
  D[i]=d
ans=0
for i in range(N):
  ans+=abs(i-D[i])
print(ans)