title: Spreadsheet : every possible combination of 2 columns into one single colum
body: <p>and sorry if this question looks familiar, I saw a lot of similar problems but couldn't understand the trick, and I completely stuck.</p>
  
  <p>I have a spreadsheet with 2 columns :</p>
  
  <p><strong>A</strong> with Countries<br>
  <strong>B</strong> with their code</p>
  
  <pre><code>  A             B
  Belgium        BE
  England        EN
  France         FR
  Luxembourg     LX
  Netherlands    NL
  Spain          SP
  </code></pre>
  
  <p>I'm trying to generate generate a matrix representing all the possible travels : Travel from A to A, from A to B, from B to A, and from B to B. <strong>The only restriction is not to travel from a country to itself</strong>.</p>
  
  <p>At the end I want to generate the result in a single column <strong>C</strong>, like this :</p>
  
  <blockquote>
    <p>Travel from Belgium to England<br> Travel from Belgium to France<br>
    Travel from Belgium to Luxembourg<br> Travel from Belgium to
    Netherlands<br> Travel from Belgium to Italy<br> Travel from Belgium
    to Spain<br> Travel from England to Belgium<br> Travel from England to
    France<br> Travel from England to Luxembourg<br> Travel from England
    to Netherlands<br> Travel from England to Italy<br> Travel from
    England to Spain<br> etc<br> Travel from Belgium to EN<br> Travel from
    Belgium to FR<br> Travel from Belgium to LX<br> Travel from Belgium to
    NL<br> etc<br> Travel from BE to EN<br> Travel from BE to FR<br>
    Travel from BE to LX<br> etc<br> Travel from BE to England<br> Travel
    from BE to France<br> etc<br></p>
  </blockquote>
  
  <p>Can anyone help me with that ? I tried several tricks with concatenation and JOIN, but I don't get anywhere ...</p>
  
  <p>Thanks a lot in advance</p>