第1个回答 2022-05-30
24点游戏结果大全_百度文库
五.4个中有一对AABC：C（1,9）*C（2,8）=9*8*7/2=252 209种有解,43种 无解 .
无解的有：
1123,1124,1125,1159,1167,1178,1179,1189,2213,2279,3324,3358,4459,4467,5513,5517,5518,5526,5569,5579,6617,6678,7715,7716,7718,7726,7729,7735,7749,7758,7768,7769,7789,8834,8867,9912,9914,9918,9925,9927,9957,9958,9978 22AB,33AB,44AB,66AB,88AB都仅各有两个无解.11AB,55AB,77AB,99AB分别各有8,6,11,8个无解.