>>141090
That's still compile time, it only works for values between 0 and 66. The array becomes as big as the highest index in it, which in that case is 66 (from 'B'), trying to use a['C'] will overflow the array and explode your house because the value of 'C' is 67. You also can't use multiple characters in a "character constant", you can't do a['LoL'], so it's kinda pointless to do it like that.

If you want to use arbitrary values then neither solution is the right thing.