How do I use bitwise operators on a “double” on C++?

Question

I was asked to get the internal binary representation of different types in C. My program currently works fine with \'int\' but I would like to use it with \"double\" and \"

Answer 1

Other solution is to get a pointer to the floating point variable and cast it to a pointer to integer type of the same size, and then get value of the integer this pointer points to. Now you have an integer variable with same binary representation as the floating point one and you can use your bitwise operator.

string findBin(float f) {
    string binary;
    for(long i = 4096 ; i >= 1; i/=2) {
        long x = * ( long * ) &y;
        if((x & i) != 0) binary += "1";
        else binary += "0";
    }
    return binary;
}

But remember: you have to cast to a type with same size. Otherwise unpredictable things may happen (like buffer overflow, access violation etc.).