A fictional alien species counts using bases other than 10, and represents digit values 10 through 35 with the uppercase letters A through Z (so A = 10, B = 11, ..., Z = 35).
Given a non-negative decimal integer n and a base b, write n in base b using this digit alphabet, with no leading zeros (except when n itself is 0, in which case the answer is just 0).
Input format
Line 1: two space-separated integers n and b.
Output format
A single string: n written in base b, most-significant digit first, using 0-9 then A-Z for digit values 10 and above.
Constraints
- 0 <= n <= 1000000000000000
- 2 <= b <= 36