Finding the bit/bits from one digit which different it from group of other digits (Kazakow method)

The method is generally called Kazakow and I'm looking for
C/C++ implementation or even help where to find it or how it may work

About the method:
We have one digit(F0) and a group of other digits(F1).

F0=0110

F1=1000,
   1001,
   0011,

We want to find the bit/bits which different F0 and F1.
The result must contains the fewest bits which different them
so the answer is -1-- (bit 3) - only one bit in this exapamle !!

_generaly for ONE bit  

for i := 1 to n do {numbers of bits}
  begin
     { here I compare F0 and F1 }
        { by the bit number i }
  end;
---------
_for TWO bit  

  for i := 1 to n-1 do
  begin
     for j :=i+1 to n do
     begin
     { here I compare F0 and F1 }
        { by the bit number "i" and bit "j"}
  end;
---------
but how to find n-bits which different them ?!
this situations accurs in Karnaugh grid where '1' is
rounded with '0'

What for this example ?!
F0=01111

F1=00111,
   01011
   01101,
   01110,
   11111

what if I have 20-bits digits ?!

I think that some sort of adding items or even recuration is here needed

Any suggestions ?

Peter