mpd: fix floating point exception when adding random tags/songs

NEWS

@@ -1,3 +1,7 @@
+ncmpcpp-0.6.3 (????-??-??)
+
+* Fix floating point exception when adding a specific number of random items.
+
 ncmpcpp-0.6.2 (2014-12-13)
 
 * Delete key now aditionally binds by default to action that deletes files in browser.

src/mpdpp.cpp

@@ -505,7 +505,7 @@ bool Connection::AddRandomTag(mpd_tag_type tag, size_t number)
 	else
 	{
 		std::random_shuffle(tags.begin(), tags.end());
-		auto it = tags.begin()+rand()%(tags.size()-number);
+		auto it = tags.begin();
 		for (size_t i = 0; i < number && it != tags.end(); ++i)
 		{
 			StartSearch(1);
@@ -546,7 +546,7 @@ bool Connection::AddRandomSongs(size_t number)
 	{
 		std::random_shuffle(files.begin(), files.end());
 		StartCommandsList();
-		auto it = files.begin()+rand()%(std::max(size_t(1), files.size()-number));
+		auto it = files.begin();
 		for (size_t i = 0; i < number && it != files.end(); ++i, ++it)
 			AddSong(*it);
 		CommitCommandsList();