INPUT "Value to convert (0 <= n <= 32767"; n
state = 0
PRINT "B ";
FOR i = 14 TO 0 STEP -1
        SELECT CASE state
        CASE 0
                IF (n AND (2 ^ i)) = 0 THEN
                        PRINT "Y ";
                        state = 2
                ELSE
                        PRINT "G ";
                        state = 1
                END IF

        CASE 1
                IF (n AND (2 ^ i)) = 0 THEN
                        PRINT "B ";
                        state = 0
                ELSE
                        PRINT "Y ";
                        state = 2
                END IF

        CASE 2
                IF (n AND (2 ^ i)) = 0 THEN
                        PRINT "B ";
                        state = 0
                ELSE
                        PRINT "G ";
                        state = 1
                END IF
        END SELECT
NEXT i
PRINT