This code first gets (almost) the binary representation of a number then it says whether to add or not based on that representation.

Example:
input:
5

output:
don't add
add

Thus, you start with 1, then you multiply by 2, then you don't add 1, then you multiply by 2, and add 1 again. You get 5.

With an input of n% = 3, you start with 1, multiply by 2, then add 1. Thus you get 3.

CLS

n% = 9



IF n% < 1 THEN PRINT "Error": SYSTEM

DO

IF n% = 1 THEN EXIT DO

IF n% AND 1 THEN n$ = "1" + n$ ELSE n$ = "0" + n$

n% = n% \ 2

i% = i% + 1

LOOP



n% = 1

FOR j% = 1 TO i%

n% = n% * 2

IF MID$(n$, j%, 1) = "1" THEN n% = n% + 1: PRINT "add" ELSE PRINT "don't add"

NEXT j%