A9645 | Vasya and Socks

Vasya has $n$ pairs of socks. In the morning of each day Vasya has to put on a pair of socks before he goes to school. When he comes home in the evening, Vasya takes off the used socks and throws them away. Every $m$ -th day (at days with numbers $m,2m,3m,...$ ) mom buys a pair of socks to Vasya. She does it late in the evening, so that Vasya cannot put on a new pair of socks before the next day. How many consecutive days pass until Vasya runs out of socks?

The single line contains two integers $n$ and $m$ $(1<=n<=100; 2<=m<=100)$ , separated by a space.

Print a single integer — the answer to the problem.