Problem: Many people are aware of DMCA – Digital Millennium Copyright Act. But another recently proposed DMCA – Digital Millennium Calculation Act – is much less known.

In this problem you need to find a root of a number according to this new DMCA law.

Input

The input contains a single integer a (1 ≤ a ≤ 1000000).

Output

Output the result – an integer number.

Examples

Input


1


Output


1


Input


81


Output


9

Solution (in PYTHON3):

Solution:
def sum(n):
	x=n
	n=""
	sum=0
	for i in x:
		sum+=int(i)
	n=str(sum)
	return n
n=input()
while len(n)!=1:
	n=sum(n)
print(n)