10 N = 5 : GOSUB 100
20 N = 50 : GOSUB 100
30 N = 9000 : GOSUB 100
40 END
90 REM *** SUBROUTINE: CONVERT DECIMAL TO BINARY
100 N2 =  ABS(INT(N))
110 B$ = ""
120 FOR N1 = N2 TO 0 STEP 0
130 :  N2 =  INT(N1 / 2)
140 :  B$ =  STR$(N1 - N2 * 2) + B$
150 :  N1 = N2
160 NEXT N1
170 PRINT B$
180 RETURN