私は、この RosettaCode チャレンジのブルート フォース実装に取り組んでいました。USAGE BINARY-DOUBLE よりも大きな数値を処理できるようにしたかったので、加算用の非常に単純な bignum ルーチンを作成しました。
特定の反復回数に制限したい場合、その回数が 9(18) より大きい場合、それは難しいことです。そこで、配列の特定の要素に 88 というアイデアを思いついたので、以下のコードを作成しました。
03 DIGITS1 OCCURS 40 TIMES PIC 9.
03 FILLER REDEFINES DIGITS1.
05 FILLER pic 9999999999.
05 FILLER pic 999999999.
05 filler pic 9.
88 EOR value 1.
05 filler pic 9999999999.
05 filler pic 9999999999.
したがって、これが唯一の方法なのか、それとも 10^20 になったときに他の方法があるのか 、まだ疑問に思っています。
これが完全な「解決策」です。めちゃくちゃですが、ほとんど機能しています。
identification division.
program-id. Program1.
data division.
working-storage section.
01 COUNTER.
03 DIGITS1 OCCURS 40 TIMES PIC 9.
03 FILLER REDEFINES DIGITS1.
05 filler pic 9999999999.
05 FILLER pic 9999999999.
05 filler pic 9999999999.
05 filler pic 999.
05 filler pic 9.
88 EOR value 1.
05 filler pic 999999.
01 INCREMENTOR.
03 DIGITS1 OCCURS 40 TIMES PIC 9.
01 ACCUMULATOR.
03 DIGITS1 OCCURS 40 TIMES PIC 9.
01 IN-NUMBER usage binary-double unsigned.
01 I USAGE BINARY-DOUBLE UNSIGNED.
01 N USAGE BINARY-DOUBLE UNSIGNED.
01 THREE-COUNTER USAGE BINARY-CHAR value 1.
88 IS-THREE VALUE 3.
01 FIVE-COUNTER USAGE BINARY-CHAR value 1.
88 IS-FIVE VALUE 5.
01 ANSWER pic x(40).
procedure division.
initialize COUNTER ACCUMULATOR incrementor.
10-MAIN-PROCEDURE.
move 1 to IN-NUMBER.
call "MOVENUMTOBIGNUM" using by content in-number
by reference incrementor.
move 1 to IN-NUMBER.
call "MOVENUMTOBIGNUM" using by content in-number
by reference counter.
PERFORM 20-INNER-LOOP WITH TEST AFTER UNTIL eor.
move ACCUMULATOR to ANSWER.
inspect answer REPLACING LEADING '0'
by space.
DISPLAY answer.
STOP RUN.
20-INNER-LOOP.
IF IS-THREE OR IS-FIVE
call "ADDBIGNUMS" using by content counter
by reference accumulator
IF IS-THREE
MOVE 1 TO THREE-COUNTER
ELSE
ADD 1 TO THREE-COUNTER
END-IF
IF IS-FIVE
MOVE 1 TO FIVE-COUNTER
ELSE
ADD 1 TO FIVE-COUNTER
END-IF
ELSE
ADD 1 TO FIVE-COUNTER END-ADD
ADD 1 TO THREE-COUNTER END-ADD
END-IF.
call "ADDBIGNUMS" using by content INCREMENTOR
by reference counter.
EXIT.
end program Program1.
identification division.
PROGRAM-ID. MOVENUMTOBIGNUM.
ENVIRONMENT DIVISION.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 num-MOD usage binary-CHAR.
01 num-DIV usage binary-DOUBLE unsigned.
01 IN-COUNTER usage binary-char.
LINKAGE SECTION.
01 num usage binary-double.
01 BIGNUM.
03 DIGITS1 OCCURS 40 TIMES PIC 9.
PROCEDURE DIVISION USING NUM BIGNUM.
10-MOVE.
move 40 to IN-COUNTER.
perform until num = 0
divide num by 10
giving num-DIV
REMAINDER num-MOD
end-divide
move num-MOD to DIGITS1 of BIGNUM(IN-COUNTER)
move NUM-DIV to NUM
subtract 1 from IN-COUNTER end-subtract
END-PERFORM.
GOBACK.
END PROGRAM MOVENUMTOBIGNUM.
*Add Bignum to Bignum, modifying second Bignum in situ
identification division.
program-id. ADDBIGNUMS.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 IN-COUNTER usage binary-char.
01 ADD-FLAG pic 9.
88 STILL-ADDING VALUE 0.
88 DONE-ADDING VALUE 9.
01 CARRIER usage binary-char.
01 REGISTER-A usage binary-char.
LINKAGE SECTION.
01 BIGNUM1.
03 DIGITS1 OCCURS 40 TIMES PIC 9.
01 BIGNUM2.
03 DIGITS1 OCCURS 40 TIMES PIC 9.
PROCEDURE DIVISION USING BIGNUM1 BIGNUM2.
10-ADD-WITH-CARRY.
move zero to CARRIER.
move 40 to IN-COUNTER.
move zero to ADD-FLAG.
perform until DONE-ADDING
add DIGITS1 of BIGNUM1(IN-COUNTER)
DIGITS1 of BIGNUM2(IN-COUNTER)
CARRIER GIVING REGISTER-A
END-ADD
move zero to CARRIER
if REGISTER-A > 9
divide REGISTER-A by 10
giving CARRIER
remainder REGISTER-A
end-divide
else
if REGISTER-A = zero
move 9 to ADD-FLAG
END-IF
end-if
if STILL-ADDING
move REGISTER-A to DIGITS1 of BIGNUM2(IN-COUNTER)
subtract 1 from IN-COUNTER end-subtract
end-if
END-PERFORM.
goback.
END PROGRAM ADDBIGNUMS.