#include <cmath>
#include <iostream>
#include <string>
#include <decimal/decimal>
#include <limits>       // std::numeric_limits


std::ostream& operator<< (std::ostream& out,
                          std::decimal::decimal64 const& value)
{
    return out << std::decimal::decimal_to_double(value);
}


int main()
{
    std::decimal::decimal64 val = 10.12345DD;
    
    std::cout << val << std::endl;



    return 0;
} 

template <typename base_t, unsigned int divider>
class custom_decimal {  
 base_t val;
public:
 base_t get_integer() const { return val / divider; }
 base_t get_fractional() const { return val % divider; }
 template <typename T> operator T() const { return get_integer(); }
 operator double() const { return (double)val/divider; }
 operator float() const { return (float)val/divider; }
 custom_decimal(double const src) : val(src*divider) {}
 template <typename T> custom_decimal(T const src) : val(src*divider) {}
 custom_decimal operator* (custom_decimal src) { src.val = src.val*val/divider; return src; }
 custom_decimal operator+ (custom_decimal src) { src.val = src.val+val; return src; }
 custom_decimal operator- (custom_decimal src) { src.val = src.val-val; return src; }
 custom_decimal operator/ (custom_decimal src) { src.val = divider*src.val/val; return src; }
};

template<typename base_t, unsigned int divider>
std::ostream& operator<< (std::ostream& out, custom_decimal<base_t, divider> const val) {
  std::string str = std::to_string(val.get_fractional() + divider);
  str = str.substr(1, str.length()-1);
  return out << val.get_integer() << "." << str;
}

typedef custom_decimal<int64_t, 100> decimal64;