Before looking at some more complex examples that will require us to develop additional techniques, we will complete Examples 4.1 and 4.2 (with don’t cares), for which we have already developed a list of prime implicants. The only thing that is different from the first example is that we only have columns for minterms included in the function—not for don’t cares. That is really what happened in the reduced table above; the columns that were eliminated correspond to minterms that became don’t cares after having chosen the essential prime implicants (as in Map Method 3).