Boyer-Moore-Horspool text searching

Delphi/Pascal

function search(pat: string; text: string): integer; var   i, j, k, m, n: integer;   skip: array [0..MAXCHAR] of integer;   found: boolean; begin   found := FALSE;   search := 0;   m := length(pat);   if m=0 then   begin     search := 1;     found := TRUE;   end;   for k:=0 to MAXCHAR do     skip[k] := m;   {*** Preprocessing ***}   for k:=1 to m-1 do     skip[ord(pat[k])] := m-k;   k := m;   n := length(text);            {*** Search ***}   while not found and (k <= n) do   begin     i := k; j := m;     while (j >= 1) do     begin       if text[i] <> pat[j] then         j := -1       else       begin         j := j-1;         i := i-1;       end;       if j = 0 then       begin         search := i+1;         found := TRUE;       end;       k := k + skip[ord(text[k])];     end;   end; end;

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function search(pat: string; text: string): integer; var   i, j, k, m, n: integer;   skip: array [0..MAXCHAR] of integer;   found: boolean; begin   found := FALSE;   search := 0;   m := length(pat);   if m=0 then   begin     search := 1;     found := TRUE;   end;   for k:=0 to MAXCHAR do     skip[k] := m;   {*** Preprocessing ***}   for k:=1 to m-1 do     skip[ord(pat[k])] := m-k;   k := m;   n := length(text);            {*** Search ***}   while not found and (k <= n) do   begin     i := k; j := m;     while (j >= 1) do     begin       if text[i] <> pat[j] then         j := -1       else       begin         j := j-1;         i := i-1;       end;       if j = 0 then       begin         search := i+1;         found := TRUE;       end;       k := k + skip[ord(text[k])];     end;   end; end;