spelled (,)
Use the intepreter
(var-to-access,value-to-set,value-to-output-int,value-to-output-char,value-while-greater-than,value-or-equals-first)
Should be fairly obvious, but note that all vars are unsigned, ungiven values default to -1, you don't output or change variables with -1, arguments are evaluated left-to-right always, and var -1 is always equal to 1, and var 0 is stdin.