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    <p>(The question initially was a failing binary search on a <code>StringList</code>, and the reason turned out to be that the list was not sorted while the search was executed. See comments on the question.) <hr> What I would do would be to keep the stringlist sorted at all times, and instead of a 'Name=Value' pair to keep the frequency of occurrence, use the <a href="http://docs.embarcadero.com/products/rad_studio/delphiAndcpp2009/HelpUpdate2/EN/html/delphivclwin32/Classes_TStrings_Objects.html" rel="nofollow"><code>Objects</code></a> property for that. This would help avoid the Integer&lt;->String conversion the code originally had and can be achieved with sth like: <code>list.Objects[i] := Pointer(f + 1);</code></p> <p><p>Use the stringlist's <a href="http://docs.embarcadero.com/products/rad_studio/delphiAndcpp2009/HelpUpdate2/EN/html/delphivclwin32/Classes_TStringList_Find.html" rel="nofollow"><code>Find</code></a> method to find out if an entry already existed or not. <code>Find</code> executes a binary search itself, you don't need 3rd party code to do that. If the item exists already, just increment the frequency. If the item does not exist, the <code>Index</code> parameter that is set by the function is the place where the item should be inserted (see the documentation link above). Call the protected method <code>InsertItem</code> to insert the new item. The reason for the <em>protected</em> call is to avoid the find method run again needlessly (see <code>TStringList.AddObject</code> function in 'classes.pas'). This would be achieved with sth. like:</p> <pre><code>type TSL = class(TStringList); var i: Integer; s: string; begin s := 'Joe'; if list.Find(s, i) then list.Objects[i] := Pointer(Integer(list.Objects[i]) + 1) else TSL(list).InsertItem(i, s, Pointer(1)); end; </code></pre> <p><br />But you really need to profile and test alternatives, otherwise it is all based on guesswork.</p> <p><strong>edit:</strong> I would like to note that if there's no adding/deleting items outside of this procedure, the stringlist's sorted property could be kept un-set, and then the <em>protected</em> hack would be unnecessary as one could use the <a href="http://docs.embarcadero.com/products/rad_studio/delphiAndcpp2009/HelpUpdate2/EN/html/delphivclwin32/Classes_TStringList_InsertObject.html" rel="nofollow"><code>InsertObject</code></a> method then.</p>
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    1. USSertac Akyuz
    1. USSertac Akyuz
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    1. COThank you Sertac, Look at my new edition.
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    2. CO@user - You're welcome and thank you for the kind words. :) You cannot use 'list.names[i]' with this solution because 'list[i]' f.i. is 'John' not 'John=3'.
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    3. COThank you again Sertac, I noted it.
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