没必要这么麻烦
by slh123bc @ 2023-10-03 13:18:38
把 $a-b=c$ 转换成 $b+c=a$
by slh123bc @ 2023-10-03 13:20:18
只二分 $a$
by slh123bc @ 2023-10-03 13:20:50