Initial commit with days 1 to 4.

day1/solver.py

@@ -0,0 +1,32 @@
+from collections import defaultdict
+
+def part1():
+    first, second = read_ids()
+    distance = sum(abs(id1 - id2) for id1, id2 in zip(first, second))
+    print(f"Total distance is: {distance}")
+
+def part2():
+    first, second = read_ids()
+
+    # Make freqmap for second list
+    freq = defaultdict(int)
+    for id in second:
+        freq[id] += 1
+
+    # Sum first list weighted by freqmap
+    similarity = sum(freq[id] * id for id in first)
+    print(f"Similarity is {similarity}")
+
+
+
+def read_ids():
+    idlist = []
+    with open("id-list") as f:
+        for line in f:
+            if line:
+                idlist.append(map(int, line.split()))
+    return map(sorted, zip(*idlist))
+
+if __name__ == '__main__':
+    part1()
+    part2()