exercise problems

In my C How To Program book, I've worked through a number of the exercises but there are 2 that I just can't seem to figure out. One exercise has a portion where I'm supposed to take a digit like 1234 and write it to the screen with 2 spaces in between like 1 2 3 4 . The other one I can't figure out is how to pass in a time and pass back the number of seconds that have passed since the last time the clock hit 12 (noon or midnight, doesn't matter). Can anyone give me any ideas on these? I'm not asking anyone to write my code, just some ideas. Thanks.