111111111/9
=(100000000+10000000+1000000... )/9
=(999999999+9999999+999999+99999+9999+999+99+9+1*9)/9
=111111111+11111111+1111111+...+111+11+1+1
=12345678+1
=12345679
规律是
123456789*9=1111111101
12345679*9= 111111111
1234569*9= 11111121
123459*9= 1111131
12349*9= 111141
1239*9= 11151
129*9= 1161
19*9= 171
9*9= 81
所以111111111/9=12345679
原式=100000000+10000000+1000000...
=999999999+9999999+999999+99999+9999+999+99+9+1*9
=9*(11111111+1111111+111111+11111+1111+111+11+1+1)
=9*12345679
所以答案12345679