Colored zeros

Толик has just learned that binary notation exists. Delighted by this, he wrote down the binary forms of the numbers 1, 2, ..., $n$ in a column. This gave the numbers 1, 10, 11, 100, 101, 110, 111, ...

After that he erased all the written ones and started studying the positions of the zeros. He chose a number $k$ and in each row, going from left to right, marked in red every $k$-th zero, starting with the first. Thus the zeros numbered $1, k + 1, 2k + 1, \ldots$ were marked. For example, if $k = 2$, $n = 56$, the rows would look like this:

(red zeros are shown in bold and underlined)

Now Толик wonders how many zeros he marked. Help him count them.

The input file contains the numbers $n$ and $k$ ($1 \le n < 2^{31}$, $1 \le k \le 30$).

The output file must contain one number: the number of red zeros.