(rs) day 10: more output formatting

(rs) day twenty-five

(rs) day twenty-four

(rs) day 23: No need for candidate hashmap

(rs) day twenty-three

(rs) day twenty-two

(rs) day 21: cleaner

(rs) day twenty-one

(rs) day 20: minor cleanup

(rs) day twenty

(c) day 19: fix max bot calculation

(c) day 19: correct max macro

(c) fix build

(rs) day 19: sparkling

(c) day nineteen

(c) some output for day 18

(rs) use debug formatting for elapsed time

(rs) day 19: arrays for everything

I suspect this is faster because the compiler can see so much more about
the arrays and will promote a [u16; 4] to a 64 bit register.

(rs) day 19: black magic

(rs) day 19: byref iteration