コンパイル時FizzBuzz

fizzbuzz.cpp

#define BOOST_MPL_LIMIT_STRING_SIZE 128
#include<iostream>
#include<boost/mpl/string.hpp>
#include<boost/mpl/fold.hpp>
#include<boost/mpl/size_t.hpp>
#include<boost/type_traits.hpp>
#include<boost/type_traits/conditional.hpp>

namespace mpl=boost::mpl;

template<int ac,int base,int exp>
struct power_core:power_core<ac*base,base,exp-1>{};
template<int ac,int base>
struct power_core<ac,base,0>{
	enum : int{val=ac};
};
template<int base,int exp>
struct power:power_core<1,base,exp>{};


template<int de,size_t i>
struct digits_core:digits_core<de+1,i/10>{};
template<int de>
struct digits_core<de,0>{
	enum : int{val=de};
};
template<int i>
struct num_digits:digits_core<0,i>{};
template<>
struct num_digits<0>{
	enum : int{val=1};
};


template<int i>
struct digit_to_char{
        enum : char{val=i+0x30};
};
template<size_t i,int place>
struct digit_at{
	enum : char{val=(i/power<10,place>::val)%10};
};
struct nullpo{
	enum : char{val='\0'};
};


template<size_t i,int place>
struct alt_char:digit_to_char<digit_at<i,place>::val>{};


template<size_t i,int offset,int numDig,bool range>
struct offset_char_core_checked{};
template<size_t i,int offset,int numDig>
struct offset_char_core_checked<i,offset,numDig,false>:nullpo{};
template<size_t i,int offset,int numDig>
struct offset_char_core_checked<i,offset,numDig,true>:alt_char<i,(numDig-offset)-1>{};

template<size_t i,int offset,int numDig>
struct offset_char_core:offset_char_core_checked<i,offset,numDig,offset< numDig>{};

template<size_t i,int offset>
struct offset_char:offset_char_core<i,offset,num_digits<i>::val>{};

template<size_t i>
struct IntToStr{
        static const char str[];
        typedef typename mpl::string<
                                offset_char<i, 0>::val,
                                offset_char<i, 1>::val,
                                offset_char<i, 2>::val,
                                offset_char<i, 3>::val,
                                offset_char<i, 4>::val,
                                offset_char<i, 5>::val,
                                nullpo::val>::type type;
};

template<size_t i>
const char IntToStr<i>::str[]={
        offset_char<i, 0>::val,
        offset_char<i, 1>::val,
        offset_char<i, 2>::val,
        offset_char<i, 3>::val,
        offset_char<i, 4>::val,
        offset_char<i, 5>::val,
        offset_char<i, 6>::val,
        offset_char<i, 7>::val,
        offset_char<i, 8>::val,
        offset_char<i, 9>::val,
        nullpo::val
};

template<class Str,class Str1>
struct concat:mpl::insert_range<Str,typename mpl::end<Str>::type,Str1>{};
template<class Str,class Str1,typename Str2>
struct concat3:mpl::insert_range<Str,typename mpl::end<Str>::type,typename concat<Str1,Str2>::type>{};

typedef typename mpl::string<'f','i','z','z'>::type fizz;
typedef typename mpl::string<'b','u','z','z'>::type buzz;
typedef typename mpl::string<'\r', '\n'>::type mpendl;
typedef typename concat<fizz, buzz>::type fizzbuzz;

template<int N>
struct FizzBuzz{
        typedef typename concat3<typename FizzBuzz<N-1>::type,
                                        typename boost::conditional<!(N%15),typename fizzbuzz::type, 
                                                typename boost::conditional<!(N%3), typename fizz::type, 
                                                        typename boost::conditional<!(N%5), typename buzz::type, 
                                                                typename IntToStr<N>::type>::type 
                                                                        >::type 
                                                                >::type,
                                                        typename mpendl::type
                                                        >::type type;
};

template<>
struct FizzBuzz<1>{
        typedef mpl::string<'1','\r','\n'>::type type;
};

int main()
{
        std::cout<<mpl::c_str<FizzBuzz<26>::type>::value<<std::endl;
}

C++ language completely differs from the C language.

#include<stdio.h>

int main()
{
    int i=1;
    for(; i<27; i++){
        if(i%15)puts("FizzBuzz");
        else if(i%5)puts("Fizz");
        else if(i%3)puts("Buzz");
        else printf("%d\n",i);
    }

    for(i=1; i<27; i++)
        printf("%d\n\0Fizz\n\0FizzBuzz\n"+(i%5?(i%3?0:4):(i%3?14:10)),i);
}