#include <iostream>
#include <ctime>
#include <string>
using namespace std;

#define USING_C

#if defined(USING_C)
    string codeLang = "C++";
#else
    string codeLang = "ASM";
#endif

#if defined(_MSC_VER)
    string compiler = "M$";
#else
    string compiler = "GCC";
#endif

unsigned int fact( unsigned int x )
{
    #if defined( USING_C )
        int sum = 1;
        for(; x; --x )
        {
            sum *= x;
        }

        return sum;
    #else // if using ASM
        #if defined(__GNUC__)
            asm
            (
                 // Exit quick if input is zero.
                "   cmp  $2, %%ebx     \n"
                "   jle   2f           \n"

                "   movl $1,    %%eax  \n" // eax is the sum.
                "1: imul %%ebx, %%eax  \n"
                "   decl %%ebx         \n"
                "   jnz  1b            \n"
                "   movl %%eax, %%ebx  \n"
                "2:                    \n"
                : "=b" ( x )
                : "b"  ( x )
                : "%eax"
            );
        #elif defined(_MSC_VER)
            __asm
            {
                mov EBX, x

                // Exit quit if input is zero.
                xor EAX, EAX
                cmp EAX, EBX
                je  A_End

                // The factorial loop:
                mov  EAX, 1 // EAX is the sum.
        A_Loop: imul EBX
                dec  EBX
                jnz  A_Loop

                mov x, EAX

         A_End:
            }
        #endif // M$ compiler
    #endif // ASM code

    return x;
}

int main()
{
    #if defined(_MSC_VER)
        clock_t timer = clock();
    #endif

    const int MAX = 99999;

    unsigned int accum = MAX;
    while( --accum )
    {
        fact( accum );
    }

    cout << "Time on " << compiler << " using " << codeLang << ": ";

    #if defined(_MSC_VER)
        // My non-M$ compiler would normally do this for me.
        // M$V$ won't, or at least isn't.
        cout << float(clock() - timer) * 0.001f << " secs" << endl;
        system("pause");
    #endif

    /*  |_____|___M$___|__GCC__|
     *  |C++__|_22.157_|_8.406_|
     *  |ASM__|_13.900_|_XXXXX_| X = Too fast to time.
     */
}