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:
n=int(input())

if(n<=9):
    print(n)
    
else:
    while(n>9):
        m=n
        s=0
        while(m!=0):
            a=m%10
            s+=a
            m=m//10
        n=s
    print(s)