Replace is with 's (removing the leading whitespace)
Don't initialize your variables to 0: they are preset to mysterious, so you can increment them with a = a--1, or usually, you can do a = a-1 and use it negated.
n's- is the shortest way to initialize a variable to one.
Some operators like + take multiple arguments, so you can abuse it like s+" "i instead of s+" "+i
turn up/turn down to round
To get x remainder y: t = x/y, turn down t, x-t*y is the remainder
Or to just check for divisibility, you can use turn up instead
In rock x with y, the with is unneeded, rock x y works
cut can split by an int, like cut "a0b0c"with 0into x