scratch.cpp

#include <stdio.h>

static  int npow2(int x)
{
    x--;
    x |= x >> 1;
    x |= x >> 2;
    x |= x >> 4;
    x |= x >> 8;
    x |= x >> 16;
    return  ++x;
}

static unsigned int flipb4(unsigned int x)
{
       x = (((x & 0xaaaaaaaa) >> 1) | ((x & 0x55555555) << 1));
       x = (((x & 0xcccccccc) >> 2) | ((x & 0x33333333) << 2));
       x = (((x & 0xf0f0f0f0) >> 4) | ((x & 0x0f0f0f0f) << 4));
       x = (((x & 0xff00ff00) >> 8) | ((x & 0x00ff00ff) << 8));
       return((x >> 16) | (x << 16));
}



static unsigned int lrot(unsigned int x, int n)
{
    return  (x << n) | (x >> -n);
}


static unsigned int rrot(unsigned int x, int n)
{
    return  (x << -n) | (x >> n);
}


union bitset
{
    unsigned int val;
    struct
    {
        unsigned char b0: 1;
        unsigned char b1: 1;
        unsigned char b2: 1;
        unsigned char b3: 1;
        unsigned char b4: 1;
        unsigned char b5: 1;
        unsigned char b6: 1;
        unsigned char b7: 1;
    } m_field[sizeof(int)];
    unsigned char data[sizeof(int)];
};


template  <typename  T, typename N> struct is_same
{
    static const bool value = false;
};


template  <class A>  struct is_same<A, A>
{
    static const bool value = true;
};

template  <class A, class B>
static inline bool IsSame()
{
    return  is_same<A, B>::value;
}

template  <class A, class B>
static inline bool IsSame(const A& a, const B& b)
{
    return  is_same<A, B>::value;
}

class A
{

};


class B
{

};

int main()
{
    A a;
    B b;

    printf("%d \r\n", IsSame<A, A>());
    printf("%d \r\n", IsSame(a, a));

    return 0;
}