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§Giant Squid
We use a trick to immediately calculate the winning turn and score for each board.
First we create a bidirectional map between each number and turn that it’s drawn. Since the
numbers are at most 2 digits we can use a fixed size array instead of a HashMap for speed.
Then for each column and row within a board, map each number to a turn and take the maximum value. This is the turn that the row or column will win. Then take the minimum of these maximum values. This is the turn that the entire board will win.
Filtering the board numbers by turn and a reverse lookup from turn to number gives the score for each board. Sort each result by turn and the answers for part 1 and part1 are the first and last values respectively.