PROGRAM print
CALL initial(#1,x)
CALL add(x)
CALL output(#1,x)
CLOSE #1
END

SUB initial(#1,x)
    OPEN #1: printer
    LET x = 150
END SUB

SUB add(x)
    LET x = x + 200
END SUB

SUB output(#1,x)
    PRINT #1: x
END SUB