I need to parse the following XML file. Absolute beginner, doesn't know how. These are some questions that I need to answer.

List All <AI> tags within the <AC n="CCC">
List only <AI> tags and its <Desc> within the <AC n="CCC">
List all <ID> tags and its <Desc> within <AI n="AAA">
etc...

This means that I need to extract differing info depending on the command line given on the command line:

Here's the 'modified' XML file:

<World n="earth" >
  <Space n="XXX" >
    <CL n="XXX">
    <Desc>CL desc</Des>
    <Other/>
       <AC n="AAA" set="n">
                <Desc>AC AAA desc</Desc>
                <AI n="AAA" set="n">
                    <Desc>AI AAA desc</Desc>
                    <ID n="AAA" set="y">
                        <Desc>AAA ID desc</Desc>
                        <What>What AAA ID </What>
                        <AR>ID_aaa</AR>
                    </ID>
                    <ID n="BBB" set="y">
                        <Desc>BBB ID desc</Desc>
                        <What>What BBB ID </What>
                        <AR>ID_bbb</AR>
                    </ID>
                </AI>
                <AI n="BBB" set="y">
                    <Desc>AI BBB desc</Desc>
                    <ID n="AAA" set="y">
                        <Desc>AAA ID desc</Desc>
                        <What>What AAA ID </What>
                        <AR>ID_aaa</AR>
                    </ID>
                </AI>
            </AC>

            <AC n="CCC" set="y">
                <AI n="AAA" set="n">
                    <Desc>AI AAA desc</Desc>
                    <ID n="AAA" set="y">
                        <Desc>AAA ID desc</Desc>
                        <What>What AAA ID </What>
                        <AR>ID_aaa</AR>
                    </ID>
                </AI>
                <AI n="AAA" set="n">
                    <Desc>AI AAA desc</Desc>
                    <ID n="AAA" set="y">
                        <Desc>AAA ID desc</Desc>
                        <What>What AAA ID </What>
                        <AR>ID_aaa</AR>
                    </ID>
                </AI>
            </AC>

        <CL n="XXX">
    <Space n="XXX" >
<World n="earth" >
[download]

tks thandi

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