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// Example program
#include <iostream>
using namespace std;

int main()
{
  unsigned int a, b;
  int sum = 0;
  cin >> a;
  cout << "Wprowadzona liczba to: " << a << endl;
  while(a > 0) {
      b = a % 10;
      a = a / 10;
      sum += b;
  }
  do {
    a = sum;
    sum = 0;
    while(a > 0) {
        b = a % 10;
        a = a / 10;
        sum += b;
    }
  } while (to_string(sum).length() > 1);
  if (sum % 3 == 0)
    cout << "podzielna przez 3" << endl;
else 
    cout << "Nie podzielna" <<endl;
}