#standards
f - file
p - pixel map
s - section separated by \n\n, string, start variable, set
r - row
c - column
h,w - height, width
i, j - row, column indices
a - character, general purpose variable
b - bool, general purpose variable
d - direction variable
e - general purpose variable
g,z - functions
n - list of numbers or number variable
m - map, memo
k,v - key, value
l - list
u - subtotal
t - total