problems A — find modulus

For a modulus problem a ~ b ~ c to have a unique solution, one of the following conditions must be true:

a < b and b > c
a > b and b < c

Even then a solution is not guaranteed to exist.

A-1:   3 ~ 8 ~ 0
A-2:   3 ~ 8 ~ 1
A-3:   3 ~ 8 ~ 2
A-4:   3 ~ 8 ~ 3
A-5:   3 ~ 8 ~ 4
A-6:   8 ~ 3 ~ 11
A-7:   8 ~ 3 ~ 10
A-8:   8 ~ 3 ~ 9
A-9:   8 ~ 3 ~ 8
A-10:   8 ~ 3 ~ 7

solutions

A-1:	3 ~	8 ~	0
A-2:	3 ~	8 ~	1
A-3:	3 ~	8 ~	2
A-4:	3 ~	8 ~	3
A-5:	3 ~	8 ~	4
A-6:	8 ~	3 ~	11
A-7:	8 ~	3 ~	10
A-8:	8 ~	3 ~	9
A-9:	8 ~	3 ~	8
A-10:	8 ~	3 ~	7