C / C++ / MFC

An engineer stores a FIFO queue of bit in an int on a platform with 32bit ints and 8-bit chars using the following C++ class
Class bit queue{
Int valid_bits;   //the number of valid bits held in queue
Int queue;        //least significant bits is most recent bit added
Public:
Bitqueue(): valid_bits(0), queue(0) {}
Void push(int val, int bsize);
Int pop(int bsize);
Int size();
};

1.Write implementation of bitqueue::size which should return the number of bits currently held in queue
2.Write an implementation of bitqueue::push which places the bsize least significant bits from val onto queue and update valid bits. An exception should be thrown in cases where data would otherwise be lost.
3.Write an implementation of bitqueue::pop which takes bsize bits from queue, provides them as the bsize least significant bits in the return value and updated valid bits. An exception should be thrown when any requested data is unavailable.