문제<\/h2>
Once Charlie decided to start a new life by deleting all files in his Downloads directory. It's easy to do that using `bash<\/code> shell! It has two useful features: the "rm<\/code>" command, which removes all files given as arguments, and patterns, which are replaced with the list of files matching them before executing the command.<\/p>`
`Charlie ran "rm <\/code>", but received an "Argument list too long<\/code>" response. Unfortunately, after bash<\/code> replaced "<\/code>" with the names of all files in the Downloads directory, it failed to run the command because it had too many arguments.<\/p>`
After some experiments, Charlie realized he can execute "rm abc<\/code>" to delete all files with names starting with "abc<\/code>" if there are at most $k<\/mi><\/mrow>k<\/math><\/span><\/span> k<\/span><\/span><\/span><\/span> such files. If more than k<\/mi><\/mrow>k<\/math><\/span><\/span> k<\/span><\/span><\/span><\/span> files match this pattern, none of them will be deleted. Of course, he can replace " abc<\/code>" with any string.<\/p> Help Charlie to find the smallest number of " rm<\/code>" commands needed to delete all files. Assume that he can only use the " rm<\/code>" command as " rm <prefix><\/code>", where <prefix><\/code> consists of lowercase English letters (and can be empty). <\/p> 입력<\/h2> The first line contains two integers n<\/mi><\/mrow>n<\/math><\/span><\/span> n<\/span><\/span><\/span><\/span> and k<\/mi><\/mrow>k<\/math><\/span><\/span> k<\/span><\/span><\/span><\/span> --- the number of files to delete, and the maximum number of files that can be deleted by one " rm<\/code>" command (1<\/mn>\leq<\/mo>n<\/mi>,<\/mo>k<\/mi>\leq<\/mo>$

Clean Up!