/diy/ - Do It Yourself

So I'm just dorking around with an arduino and a MAX7219. Messing with 8 segment displays. I'm real green with this stuff so I don't know all the functions.

These max ICs let you update just one digit and let the others persist. Say I was making this a counter. Is there an easy way to figure out which numbers in a string change? Say the number I have stored to display is 5000. Then A number changes to make 5010. Is there a way to say 'Hey, just the ten's place changed' or would I just have to do the N % 10, (N/10) % 10, (N/100) % 10, etc and test each number individually? I don't have a problem doing that if I need to, just wondering if there was something out there that would make checking numbers easier without having do deconstruct it each time.