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:
import sys
INP = lambda: sys.stdin.readline().strip()
INT = lambda: int(INP())
MAP = lambda: map(int, INP().split())
ARR = lambda: [int(i) for i in INP().split()]
def JOIN(arr, x=' '): return x.join([str(i) for i in arr])
def EXIT(x='NO'): print(x); exit()

x = INP()
while len(x)>1:
    x = str(sum([int(i) for i in x]))
print(x)