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 math

def digital_root(num):
    if(num < 10):
        return num
    
    tmp = 0
    while(num>0):
        #print(tmp,num)
        tmp += num%10
        num //= 10
    return digital_root(tmp)

while(True):
    try:
        num = int(input())
        ans = digital_root(num)
        print(ans)
    except EOFError:
        break