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d1/README.md

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+Advent of code 2024
+
+Day 1
+
+Usage:
+
+    rustc d1p1.rs
+    cat input.txt | ./d1p1
+
+Part 1:
+
+Parse each line into a pair of ints; store them in a pair of heaps.
+Convert heaps into sorted lists. Iterate through them together
+and find the absolute difference between each pair of numbers.
+
+Part 2:
+
+Parse each line into a pair of ints; store the first in an array,
+place the second into a map that accumulate the number of times
+a value is seen.
+
+Iterate through the array, adding the number times the number of
+times it was seen in the map.
+