Program in qbasic to check binary or not

CLS
DIM N AS INTEGER,D AS INTEGER
INPUT"ENTER ANY NUMBER";N
WHILE N>0

D=N MOD 10

IF D< >0 THEN
       IF D< >1 THEN
             PRINT"NOT BINARY NUMBER"
             END
       END IF
END IF

WEND
PRINT"BINARY NUMBER"
END