Petya has *k* matches, placed in *n* matchboxes lying in a line from left to right. We know that *k* is divisible by *n*. Petya wants all boxes to have the same number of matches inside. For that, he can move a match from its box to the adjacent one in one move. How many such moves does he need to achieve the desired configuration?
The first line contains integer *n* (1 ≤ *n* ≤ 50000). The second line contains *n* non-negative numbers that do not exceed 10<sup class="upper-index">9</sup>, the *i*-th written number is the number of matches in the *i*-th matchbox. It is guaranteed that the total number of matches is divisible by *n*.
a=[]

def main():
	n=int(input())
	a.append(0)
	B=input()
	for x in B.split():
		a.append(int(x))
	a.append(0)
	S=sum(a)
	ave=float(S)/n
	ans=0
	for i in range(1,n+1,1):
		if a[i] < ave:
			ans += ave-a[i]
			a[i+1] -= ave-a[i]
		else:
			ans += a[i]-ave
			a[i+1] += a[i]-ave
	print(int(ans))

main()