#include <algorithm> // reverse
#include <climits>   // CHAR_BIT
#include <iostream>
#include <sstream>

std::string binario(unsigned int n)
{
  //converte numero para string de bits
   std::stringstream bitsInReverse;
   //int nBits = sizeof(n) * CHAR_BIT;
   unsigned int nBits = sizeof(n)*2.5;

   while (nBits-- > 0)
   {
      bitsInReverse << (n & 1);
      n >>= 1;
   }

   std::string bits(bitsInReverse.str());
   std::reverse(bits.begin(), bits.end());
   return bits;
}


struct Bin
{
  friend std::ostream& operator<<(std::ostream& os, const Bin& f);
  int a;
}bin;

std::ostream &operator<<( std::ostream &saida, const Bin& f)
{
  int c(f.a);
  //converte numero para string de bits
   std::stringstream bitsInReverse;
   //int nBits = sizeof(c) * CHAR_BIT;
   unsigned int nBits = sizeof(c) * 3;

   while (nBits-- > 0)
   {
    bitsInReverse << (c & 1);
    c >>= 1;
   }

   std::string bits(bitsInReverse.str());
   std::reverse(bits.begin(), bits.end());

   saida << bits;
   return saida;
}

int main()
{
    std::cout<< "\n\t127 em binario:     " << binario(127)
             << "\n\t127 em octal:       " << std::oct << 127
             << "\n\t127 em hexadecimal: " << std::hex << 127
             << "\n\t127 em decimal:     " << std::dec << 127
             << "\n\t127 em binario:     " << bin<<127<<"\n\n";
}