C 
                       B   D
                     A      E
                   o         F
                     K      G
                       J  H 
                        I

The diagram above represents a dial on a safe which has 12 points, one of them white (denoted by o). This white point, is to be turned to each letter in turn, but not in alphabetical order, to open the safe. The dial should be turned toward the letters as follows:

1. A before D but after B.
2. B before C but after H.
3. H before F, F before G, G before I and I before J.
4. H after K, K before F, F after D, D before G, and G after E.
5. E before D, C before E, E after B, C before G, and A after E.

What is the order of letters to which the white point should be turned in order to open the safe?

DECLARE SUB addOn ()
CLEAR , , 25000
DIM SHARED used(11), alpha AS STRING, h AS STRING

alpha = "abcdefghijk"

CLS

h = ""

addOn

SUB addOn
FOR i = 1 TO 11
    IF used(i) = 0 THEN
        l$ = MID$(alpha, i, 1)
        IF INSTR(h, l$) = 0 THEN
            good = 1
            SELECT CASE l$
                CASE "a"
                    IF INSTR(h, "b") = 0 OR INSTR(h, "d") > 0 THEN good = 0
                    IF INSTR(h, "e") = 0 THEN good = 0
                CASE "b"
                    IF INSTR(h, "h") = 0 OR INSTR(h, "c") > 0 THEN good = 0
                CASE "c"
                    IF INSTR(h, "e") > 0 OR INSTR(h, "g") > 0 THEN good = 0
                CASE "d"
                    IF INSTR(h, "g") > 0 THEN good = 0
                CASE "e"
                    IF INSTR(h, "d") > 0 OR INSTR(h, "b") = 0 THEN good = 0
                CASE "f"
                    IF INSTR(h, "d") = 0 OR INSTR(h, "g") > 0 THEN good = 0
                CASE "g"
                    IF INSTR(h, "e") = 0 OR INSTR(h, "i") > 0 THEN good = 0
                CASE "h"
                    IF INSTR(h, "f") > 0 OR INSTR(h, "k") = 0 THEN good = 0
                CASE "i"
                    IF INSTR(h, "j") > 0 THEN good = 0
            END SELECT
            IF good THEN
                h = h + l$
                IF LEN(h) = 11 THEN
                    PRINT h
                ELSE
                    addOn
                END IF
                h = LEFT$(h, LEN(h) - 1)
            END IF

        END IF
    END IF
NEXT
END SUB

finds the order as

khbceadfgij

 

Posted by Charlie on 2013-09-09 17:29:58