advent-of-code/2021/14

14

This was nice! Similar to the Lanterfish one. The naive way is to have a big string, but that becomes unfeasible quickly.

The solution was to keep track of the number of combinations available and at the end divide by 2 the counted elements. Rounding up so that the first and last element is not neglected as they are not doubled.

Solutions

1. 2988
2. 3572761917024