There are two distinct oneinput logic operations and eight distinct twoinput operations. The tables below show the output obtained by performing each of these operations on each possible bitwise input. The bottom rows indicate the minimum number of nand computations required to perform each operation, proven through exhaustive search. To receive the reward for doing a particular logic function, a digital organism must return the correct values for an entire series of 32 bitwise problems, including multiple examples of each possible combination of inputs.


* The order of the two inputs is arbitrary. Thus, the rewards for performing OR_N and AND_N are also triggered by the recipricol operations, in which A and B are reversed.
From the Supplementary Information for an article by Lenski, Ofria, Pennock & Adami on "The Evolutionary Origin of Complex Features" that appeared in Nature (8 May 2003), vol 423, pp 139144.