#include <iostream>
#include <string>
#include <vector>

class C {
  std::vector<char> line[2];
public:
  C(std::string s) {
    int j = 0;
    for (unsigned int i = 0; i < s.length(); i++)
      if (s[i] != ' ')
        line[(j++ % 2)].push_back(s[i]);
  }
  friend std::ostream &operator<<(std::ostream &s, C obj) {
    std::vector<char>::iterator p = obj.line[0].begin();
    for (;p != obj.line[0].end(); p++)
      s << *p << ' ';
    s << std::endl << ' ';
    p = obj.line[1].begin();
    for (;p != obj.line[1].end(); p++)
      s << *p << ' ';
    return s;
  }
};

int main() {
  C a("123456789"), b("The earth turns around the sun.");
  std::cout << a << std::endl;
  std::cout << b << std::endl;
  return 0;
}
/* end */

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