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POMerging multiple lists
 

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    <p>Given that there I have a list of lists, <code>List<code>&lt;List&lt;T&gt;&gt;</code></code>, in which all lists contain 0 or more items, likely, but not necessarily all the same number. And I would like tho have a list containing all the items in the Lists... but I want the order to be as follows: first the first items off all the lists, in order that they appear in the 'super-list'.</p> <p>Ex.</p> <pre><code>List[0] = { 'Apple', 'Blueberry', 'Cranberry' } List[1] = { 'Anteater', 'Baboon', 'Camel', 'Dodo'} List[2] = { 'Albatross', 'Blackbird', 'Chicken'} result = { 'Apple', 'Anteater', 'Albatross', 'Blueberry', 'Baboon', 'Blackbird', 'Cranberry', 'Camel', 'Chicken', 'Dodo' } </code></pre> <p>(note that this is NOT alphabetical order, Blueberry comes before Baboon)</p> <p>Ofcourse, i could just loop through the 'superlist' with a counter, adding items to the resultslist one by one, as long as there is a list that isn't empty:</p> <pre><code>int i = 0; bool done = false; while (!done) { bool found = false; foreach (list l in superlist) { if (l.Count() &gt; i) { found = true; result.Add(l[i]); } } i++; if (!found) done = true; } </code></pre> <p>But it would be way nicer to use some optimized LINQ function to do this. I have been looking into <a href="http://msdn.microsoft.com/en-us/library/dd267698.aspx" rel="nofollow">Zip</a>, <a href="http://msdn.microsoft.com/en-us/library/system.linq.enumerable.groupby.aspx" rel="nofollow">GroupBy</a> and <a href="http://msdn.microsoft.com/en-us/library/system.linq.enumerable.aggregate.aspx" rel="nofollow">Aggregate</a>, but couldn't get them to work.</p> <p>So: Is there a pretty LINQ function, or combination of multiple, that would turn this into pretty code, or should I stick by (and maybe optimize) my current function?</p> <p>Edit: A simple SelectMany(x => x) also doesn't do the trick, as it preserves the order of the lists, instead of folding them, like my algorithm does. See my initial question for more details.</p>
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    1. CODuplication of this: http://stackoverflow.com/questions/1590723/flatten-list-in-linq
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    2. CONot a duplicate of above link, read complete question
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