-- Purpose:   Compute the minimal edit distance between two strings over a
--            given alphabet. Edit operations: insert, delete, replcae. 
--            All operations have the same cost.
-- Algorithm: The routine uses the O(m*n) dynamic programming solution
-- Reference: The algorithm is described in "Introduction to Algorithms", Udi
--            Manber
------------------------------------------------------------------------------
--  Ehud Lamm, 1999
------------------------------------------------------------------------------
generic
   type Alphabet is private;
   type String_Index is (<>);
   type String_Type is array(String_Index range <>) of Alphabet;
function Minimal_Edit_Distance(S1,S2:String_Type) return Natural;