lt=info src=/images/info.svg> <em>To run the solutions, use <code>mawk -f script.awk list.txt ip.txt</code></em><p><strong>In my dreams that night</strong>, I realized that the solution can be improved drastically by looping over the digits after <code>clear_number=</code> instead of looping over keys saved in <code>arr</code>. Matching a key is <code>O(1)</code>, so the time saving is huge since the inner loop is now a maximum of 12 (length of digits after <code>clear_number=</code>) instead of looping a m