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:
num = input()
ans = 10
while ans>9:
    ans = 0
    for ch in num:
        ans += (ord(ch)-ord('0'))
    if ans>9:
        num = str(ans)

print(ans)