function LevenshteinDistance(s, t : String) : Integer;
var
   i, j : Integer;
begin
   var d:=new Integer[Length(s)+1, Length(t)+1];
   for i:=0 to Length(s) do
      d[i, 0] := i;
   for j:=0 to Length(t) do
      d[0, j] := j;

   for j:=1 to Length(t) do
      for i:=1 to Length(s) do
         if s[i]=t[j] then
            d[i, j] := d[i-1, j-1] // no operation
         else d[i,j]:=MinInt(MinInt(
               d[i-1, j] +1 ,    // a deletion
               d[i, j-1] +1 ),   // an insertion
               d[i- 1,j-1] +1    // a substitution
               );
   Result:=d[Length(s), Length(t)];
end;

PrintLn(LevenshteinDistance('kitten', 'sitting'));