A/a,B/b,C/c,D/c,共有四组变量,两两交叉后总共有16种(2x2x2x2),请帮助排列下。实现的大致效果,比如:ABCD,AbCD,aBCD,
const a:array[0..3]of integer=(1,2,4,8);
var i,j:integer;
begin
for i:=0 to 15 do
for j:=0 to 3 do
write(chr(65+j+ord(i and a[j]>0)*32));
writeln;
end;
end.