NAND gates

NOT

!A

!(A & A)

AND

A & B

!!(A & B)

OR

A | B

!!(A | B)

!(!A & !B)

XOR, 6 gates

(A | B) & !(A & B)

XOR, 5 gates

(A & !B) | (!A & B)

!!((A & !B) | (!A & B))

!(!(A & !B) & !(!A & B))

XOR, 4 gates

(A & !B) | (!A & B)

(A & !A) | (A & !B) | (B & !A) | (B & !B)

A & (!A | !B) | B & (!A | !B)

A & !(A & B) | B & !(A & B)

!(!(A & !(A & B)) & !(B & !(A & B)))

NOR

XNOR