Cannot convert from 'string' to 'system.collections.generic.list string'
<p>I have the two list</p>

<ol>
<li>nested list of string, and</li>
<li>list in string</li>
</ol>

<p>In <code>index</code> list, I want to add <code>linesOfContent</code>with a <code>common</code> value and in-between i want to add separate string <code>":"</code>. </p>

<p>For that i write a code, but, I face a problem "cannot convert from 'string' to 'system.collections.generic.list string'". How to solve this.</p>

<pre><code>int common = 10;
List&lt;List&lt;string&gt;&gt; index = new List&lt;List&lt;string&gt;&gt;();
List&lt;int&gt; linesOfContent = new List&lt;int&gt;();
for(int i = 0; i &lt; 5; i++)
{
      for(int j = 0; j &lt; 5; j++)
      {       
             linesOfContent.Add(i+":"+common);
      }
      index.Add(linesOfContent);
}
</code></pre>

<p><strong>Expected Output:</strong></p>

<pre><code>index[0][0] = 0:10
index[0][1] = 1:10
index[0][2] = 2:10
</code></pre>

<p>...
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