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 PYTHON):

Solution:
import sys
range = xrange
input = raw_input

def f(A):
    x = sum(int(x) for x in A)
    if x > 9:
        return f(str(x))
    return x
print f(input())