Data commit

Task/Levenshtein-distance/Delphi/levenshtein-distance.delphi

@@ -0,0 +1,63 @@
+program Levenshtein_distanceTest;
+
+{$APPTYPE CONSOLE}
+
+{$R *.res}
+
+uses
+  System.SysUtils,
+  Math;
+
+function Levenshtein_distance(s, t: string): integer;
+var
+  d: array of array of integer;
+  i, j, cost: integer;
+begin
+  SetLength(d, Length(s) + 1);
+  for i := Low(d) to High(d) do
+  begin
+    SetLength(d[i], Length(t) + 1);
+  end;
+
+  for i := Low(d) to High(d) do
+  begin
+    d[i, 0] := i;
+    for j := Low(d[i]) to High(d[i]) do
+    begin
+      d[0, j] := j;
+    end;
+  end;
+
+  for i := Low(d) + 1 to High(d) do
+  begin
+    for j := Low(d[i]) + 1 to High(d[i]) do
+    begin
+      if s[i] = t[j] then
+      begin
+        cost := 0;
+      end
+      else
+      begin
+        cost := 1;
+      end;
+
+      d[i, j] := Min(Min(d[i - 1, j] + 1,      //deletion
+        d[i, j - 1] + 1),     //insertion
+        d[i - 1, j - 1] + cost  //substitution
+      );
+    end;
+  end;
+  Result := d[Length(s), Length(t)];
+end;
+
+procedure Println(s, t: string);
+begin
+  Writeln('> LevenshteinDistance "', s, '" "', t, '"');
+  Writeln(s, ' -> ', t, ' = ', Levenshtein_distance(s, t), #10);
+end;
+
+begin
+  Println('kitten', 'sitting');
+  Println('rosettacode', 'raisethysword');
+  readln;
+end.