Problem:
Score : 200 points

Problem Statement

An integer N is a multiple of 9 if and only if the sum of the digits in the decimal representation of N is a multiple of 9.

Determine whether N is a multiple of 9.

Constraints

0 \leq N < 10^{200000}

N is an integer.

Input

Input is given from Standard Input in the following format:

N

Output

If N is a multiple of 9, print Yes; otherwise, print No.

Sample Input 1

123456789

Sample Output 1

Yes

The sum of these digits is 1+2+3+4+5+6+7+8+9=45, which is a multiple of 9, so 123456789 is a multiple of 9.

Sample Input 2

0

Sample Output 2

Yes

Sample Input 3

31415926535897932384626433832795028841971693993751058209749445923078164062862089986280

Sample Output 3

No

Solution in C++ (GCC 9.2.1) (judge verdict: Accepted)

#include <iostream>
#include <cmath>
#include <stdio.h>
using namespace std;
bool is_integer(double x)
{
  return floor(x) == ceil(x);
}
int main()
{
  int sum = 0;
  char c;

  while (true)
  {
    cin.get(c);
    if (c == '\n')
    {
      break;
    }
    sum += atoi(&c);
  }

  // for (;;)
  // {
  //   sum += n % 10;
  //   n = n / 10;
  //   if (n == 0)
  //     break;
  // }
  if (sum % 9 == 0)
  {
    cout << "Yes" << endl;
  }
  else
  {
    cout << "No" << endl;
  }
}