A finite word $f$ is Hamming-isometric if for any two word $u$ and $v$ of same length avoiding $f$, $u$ can be transformed into $v$ by changing one by one all the letters on which $u$ differs from $v$, in such a way that all of the new words obtained in this process also avoid~$f$. Words which are not Hamming-isometric have been characterized as words having a border with two mismatches. We derive from this characterization a linear-time algorithm to check whether a word is Hamming-isometric. It is based on pattern matching algorithms with $k$ mismatches. Lee-isometric words over a four-letter alphabet have been characterized as words having a border with two Lee-errors. We derive from this characterization a linear-time algorithm to check whether a word over an alphabet of size four is Lee-isometric.
翻译:限定单词$f$是Hamming-issotery, 如果对任何两个单词来说,只要一个单词是$u$, 美元长度是相同的, 避免$f$, 美元就可以转换成$v$, 其方法是将所有美元与$v$不同的字母一一一换成美元, 其方式是使在这一过程中获得的所有新单词也避免~f$。 不是Hamming- issotery的单词被定性为具有两个不匹配的边框的单词。 我们从这个描述线性时间算法中得出一个线性时算法, 以检查一个单词是否是 Hamming- isology。 它基于模式将算法与 $k$不符的对等算法。 四字母字母的单词被定性为与两个 Lee- erors 的边框的单词。 我们从这个描述线性时算算法来检查一个四号上的单词是否是 Lee- asimter。
Alphabet is mostly a collection of companies. This newer Google is a bit slimmed down, with the companies that are pretty far afield of our main internet products contained in Alphabet instead.https://abc.xyz/