PUBLIC NUMERIC C                   !解の数
LET C=0
DIM T(9)
CALL backtrack(T,1,0)
IF C=0 THEN PRINT "解なし"
PRINT
PRINT "このプログラムは終了しました。"
END


EXTERNAL SUB backtrack(T(),p,sm)
FOR i=1 TO 9
   FOR k=1 TO p-1                  !同じ数字かどうか
      IF T(k)=i THEN EXIT FOR
   NEXT k
   IF k>p-1 THEN
      LET T(p)=i
      LET X=0
      IF p=9 THEN
         IF T(1)+T(2)+T(3)+T(4)<>T(6)+T(7)+T(8)+T(9) THEN 
            LET X=1
         ELSEIF T(1)>T(2) OR T(2)>T(3) OR T(3)>T(4) THEN 
            LET X=1
         ELSEIF T(6)>T(7) OR T(7)>T(8) OR T(8)>T(9) THEN
            LET X=1 
         END IF
      END IF
      IF X=0 THEN
         IF p=9 THEN
            LET C=C+1
            PRINT "No.";C
            PRINT
            FOR s=1 TO 4
               PRINT T(s);
            NEXT s
            PRINT "   ";T(5);"   ";
            FOR s=6 TO 9
               PRINT T(s);
            NEXT s
            PRINT
            PRINT
         ELSE
            CALL backtrack(T,p+1,sm)               ! 再帰
         END IF
      END IF
   END IF
NEXT i
END SUB