Template:ClassMatrix

{{#lua:

 local H = {};
 for id in stdin:gmatch("%w+") do
   str = string.sub(id,{{{2}}},{{{3}}});
   if (H[str] == nil) then H[str] = 1;
     else H[str] = H[str] + 1;
   end
 end
 for k,v in pairs(H) do
   print(k .. v);
 end

| }}