%s1=('a'=>1, 'b'=>1, 'c'=>1); %s2=('a'=>1, 'c'=>1, 'd'=>1); print "Set 1 has: ", join(",",keys %s1), " Set 2 has: ", join(",", keys %s2),"\n"; %j=%s1; @j{keys %s2}=1; print "Union is ", join(",", keys %j), "\n";