Hopscotch

Had a good, productive math day on a topic that just popped into my head this morning. I love when that happens. Gonna keep it short today.

I saw this sparrow contemplating a game of hopscotch:

 And this guy cleaning windows at the bank:

Sevilla's not the cleanest city I've ever been in (Vienna), but they do a pretty good job of keeping the centro clean. It's tough to keep the streets clean when it never rains. Also, like Budapest, graffiti. I don't get graffiti. Specifically, why is it so prevalent in some places and non-existent in other places? I guess that's a question for sociologists.