Base Conversion 2

A number $N$ written in base 10 is given. Write a program that converts it to base $B$ and prints the result.

In a base above 10, some digits cannot be written with the characters 0 to 9. Those digits use uppercase letters. A is 10, B is 11, and in the same way F is 15, Y is 34, and Z is 35.

The first line contains $N$ and $B$, separated by a space. $N$ is a natural number no greater than one billion, and $B$ is an integer with $2 \le B \le 36$.

Print $N$ written in base $B$ on the first line. Write digits above 9 as uppercase letters, and do not add leading zeros.