public IEnumerable <string> Transform(string start, string end, bool substitutionsOnly)
{
Validate.IsNotNullOrEmpty(start);
Validate.IsNotNullOrEmpty(end);
Validate.IsTrue(
!substitutionsOnly || start.Length == end.Length,
"When only substitutions are allowed, the start and end words must be the same length.");
if (substitutionsOnly)
{
return(RestrictedGraphSearcher.FindPath(
start,
end,
word => EditDistance.CalculateHamming(word, end)
));
}
else
{
return(FullGraphSearcher.FindPath(
start,
end,
word => EditDistance.CalculateLevenshtein(word, end)
));
}
}
private void AddValidEdges(IEnumerable <Tuple <string, string> > wordPairs)
{
foreach (var pair in wordPairs)
{
string a = pair.Item1;
string b = pair.Item2;
if (EditDistance.AreLevenshteinAdjacent(a, b))
{
AddEdge(a, b);
AddEdge(b, a);
}
}
}