<ul><li>In Part 1, the author uses regex to find all instances of mul(N,N) and performs the appropriate extraction and math for each match.</li><li>For Part 2, the author uses regex to match do() and don't() occurrences and then isolates each stretch of valid statements to check for mul statements to parse.</li><li>The author implements an algorithm to handle various conditions, finds the start and end indices for each substring, and calculates the muls in the substrings.</li><li>The code generates the correct answer for both the example input and the author's puzzle input.</li></ul>

Mull It Over

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