def xor(a, b): return aand(nand(a,b),oor(a,b))
def xor(a, b): return aand(nand(a, b), oor(a, b))
def nor(a, b): return nnot(oor(a,b))
def fulladder(a, b, c): return {'c':oor(halfadder(a,b)['c'],halfadder(halfadder(a,b)['o'],c)['c']),'o':halfadder(halfadder(a,b)['o'],c)['o']}
def nor(a, b): return nnot(oor(a, b))