一道数字题,谁会?(张小灿问)

共计504个
321-3-2-1=315 421-4-2-1=414 521-5-2-1=513 621-6-2-1=612
721-7-2-1=711 821-8-2-1=810 921-9-2-1=909 231-2-3-1=225
431-4-3-1=423 531-5-3-1=522 631-6-3-1=621 731-7-3-1=720
831-8-3-1=819 931-9-3-1=918 241-2-4-1=234 341-3-4-1=333
541-5-4-1=531 641-6-4-1=630 741-7-4-1=729 841-8-4-1=828
941-9-4-1=927 251-2-5-1=243 351-3-5-1=342 451-4-5-1=441
651-6-5-1=639 751-7-5-1=738 851-8-5-1=837 951-9-5-1=936
261-2-6-1=252 361-3-6-1=351 461-4-6-1=450 561-5-6-1=549
761-7-6-1=747 861-8-6-1=846 961-9-6-1=945 271-2-7-1=261
371-3-7-1=360 471-4-7-1=459 571-5-7-1=558 671-6-7-1=657
871-8-7-1=855 971-9-7-1=954 281-2-8-1=270 381-3-8-1=369
481-4-8-1=468 581-5-8-1=567 681-6-8-1=666 781-7-8-1=765
981-9-8-1=963 291-2-9-1=279 391-3-9-1=378 491-4-9-1=477
591-5-9-1=576 691-6-9-1=675 791-7-9-1=774 891-8-9-1=873
312-3-1-2=306 412-4-1-2=405 512-5-1-2=504 612-6-1-2=603
712-7-1-2=702 812-8-1-2=801 912-9-1-2=900 132-1-3-2=126