|You can produce the sequence (in slight different order) this way:
const char sSequence="abcd";
len = (int) strlen(sSequence);
for (int i=0; i<len; i++)
for (int j=0; i<len; j++)
printf("%c%c\n", sSequence[i], sSequence[j]);
If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.
This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke