PRINT
INPUT PROMPT "２０桁までの数を入力   ":n$
PRINT
DIM A$(35),B$(35),C$(35)
LET m=LEN(n$)
LET Z=0
FOR i=m TO 1 STEP -1
   LET A$(m-i+1)=mid$(n$,i,1)      ! i 番目の文字を取り出す
NEXT i
LET q=1
FOR i=1 TO m+INT((m-1)/4)
   IF MOD(q,5)=0 THEN
      LET C$(q)=","
      GOTO 10
   END IF 
   LET C$(q)=A$(i-INT(q/5))
10    LET q=q+1
   NEXT i
   LET j=1
   FOR i=1 TO m+INT((m-1)/3)
      IF MOD(j,4)=0 THEN
         LET B$(j)=","
         GOTO 20
      END IF 
      LET B$(j)=A$(i-INT(j/4))
20    LET j=j+1
   NEXT i
   PRINT "   ";
   FOR i=q-1 TO 1 STEP -1
      IF C$(q-1)="," THEN
         LET C$(q-1)="0"
         GOTO 30
      END IF
      PRINT C$(i);
30 NEXT i
   PRINT
   PRINT
   PRINT "      千百十＿ :  京　兆　億　万"
   PRINT
   PRINT
   PRINT "   ";
   FOR i=j-1 TO 1 STEP -1
      IF B$(j-1)="," THEN 
         LET B$(j-1)="0"
         GOTO 40
      END IF 
      PRINT B$(i);
40 NEXT i
   PRINT
   PRINT
   PRINT "      hundred and ＿ ：  quintillion   quadrillion   trillion"
   PRINT "                                       billion   million   thousand"
   PRINT
END