#include <iostream>
using namespace std;

int main() {
  cout.setf(std::ios::dec, std::ios::basefield);
  cout << 30 << endl;
  
  cout.setf(std::ios::oct, std::ios::basefield);
  cout << 30 << endl;
  
  cout.setf(std::ios::hex, std::ios::basefield);
  cout << 30 << endl;
  
  cout << std::dec << 30 << endl;
  cout << std::oct << 30 << endl;
  cout << std::hex << 30 << endl;
}