Since this smells of homework, I'll be brief. You'll need a split and a loop, and to do an append, if you want the first element to contain everything in the first columm, etc. That much should lead you to the answer, with some thought.

Failing that, I am adding an additional hint from a CB discussion with broquaint, but try this for yourself first-you will gain more from the thought involved than you may realize.

split the string char for char, then append it to the array with its position.... as long as all strings are the same length.... hrm...