Python Subtracting Elements in a Lists from Previous Element
<p>I have a loop that produces multiple lists such as these:</p>

<pre><code>  [1,6,2,8,3,4]

  [8,1,2,3,7,2]

  [9,2,5,6,1,4]
</code></pre>

<p><em>For each list, I want to subtract the first two elements, and then use that value to then subtract the third element from.</em> </p>

<p>For example, the first list should end up looking like:</p>

<pre><code>  [-5, 4,-6, 5,-1]
</code></pre>

<p>I have tried to manually do this, but there are too many lists to do this and it would take too much time. </p>

<p>How would I do that in the least amount of lines of code?</p>