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 JAVA):

Solution:
var x = readline();

function sumDigits(num) {
  num = num.toString().split('');
  n = 0;

  for (var i = 0; i < num.length; i++) {
    n += Number(num[i]);
  }

  if (n < 10) return n;
  else return sumDigits(n);
}

print(sumDigits(x));