Problem I. Illumination overlap

Author:M. Sporyshev   Time limit:1 sec
Input file:input.txt   Memory limit:256 Mb
Output file:output.txt  

Statement

The road is a straight line. A segment of the road between points A and B is N meters long and fully illuminated by several street lamps. Each lamp can be located at any (not necessarily integer) point along the road and illuminates a segment exactly M meters long, including endpoints. If any single lamp would be turned off, at least some part of the road segment between A and B will not be illuminated any more. Lamps do not illuminate parts of the road outside of segment from A to B.

Your program must calculate maximum possible number of lamps which could be put on the road while still satisfying the conditions above.

Picture illustrates sample 3.

Input file format

Input file contains integers N M.

Output file format

Output file must contain a single integer — maximum number of lamps.

Constraints

1 ≤ M ≤ N ≤ 109

Sample tests

No. Input file (input.txt) Output file (output.txt)
1
3 2
2
2
1000 1
1998
3
8 2
6

0.120s 0.014s 15