title: How do I dynamically change input cell in a formula based on the value in another cell in a spreadsheet?
body: <p>It is possible to dynamically change the input cell address in a formula based on the content in another cell?</p>
  
  <p>Let's say I have a spreadsheet (excel or libreoffice) with these cell values:</p>
  
  <pre><code>A1: 10
  A5:  9
  C1:  5
  </code></pre>
  
  <p>Instead of hardcoding <code>=A1-A5</code> , I would like to do something like this: <code>=A1-A(C1)</code>, that would be evaluated at run time to use cell <code>A5</code> for the second input. </p>