While the characters with diacritical marks are considered separate letters, vowels that differ only in length are treated the same when ordering words. Therefore, for example, the pairs O/Ó and Ö/Ő are not distinguished in ordering, but Ö follows O. In cases where two words are differentiated solely by the presence of an accent, the one without the accent is put before the other one. (The situation is the same for lower and upper-case letters: in alphabetical ordering,
varga is followed by
Varga.) The polygraphic consonant signs are treated as single letters. The simplified geminates of multigraphs (see above) such as <nny>, <ssz> are
collated as <ny>+<ny>, <sz>+<sz> etc.,
if they are double geminates, rather than co-occurrences of a single letter and a geminate. :
könnyű is collated as <k><ö><ny><ny><ű>.
tizennyolc of course as <t><i><z><e><n><ny><o><l><c>, as this is a
compound:
tizen+
nyolc ('above ten' + 'eight' = 'eighteen'). Similar 'ambiguities', which can occur with compounds (which are highly common in Hungarian) are dissolved and collated by sense. :e.g.
házszám 'house number (address)' =
ház +
szám and of course not *
házs + *
zám. These rules make Hungarian alphabetic ordering algorithmically difficult (one has to know the correct segmentation of a word to sort it correctly), which was a problem for computer software development. == Keyboard layout ==