feat: day 2 completed

README.md

@@ -2,4 +2,5 @@
 
 See: https://adventofcode.com/2024
 
-- [Day 1: Historian Hysteria](day_1/README.md)
+- [Day 1: Historian Hysteria](day_1/README.md)
+- [Day 2: Red-Nosed Reports](day_2/README.md)

day_2/README.md

@@ -0,0 +1,3 @@
+# --- Day 2: Red-Nosed Reports ---
+
+See: https://adventofcode.com/2024/day/2

day_2/example.txt

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+7 6 4 2 1
+1 2 7 8 9
+9 7 6 2 1
+1 3 2 4 5
+8 6 4 4 1
+1 3 6 7 9

day_2/main.py

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+from typing import List, TextIO
+
+
+def read_input(f: TextIO) -> List[int]:
+    for line in f:
+       yield [int(n) for n in line.strip().split()]
+
+
+def is_safe(report: List[int]) -> bool:
+    increasing = True
+    for j in range(0, len(report)):
+        n1, n2 = report[j], report[j + 1]
+
+        if n1 == n2:
+            return False
+
+        increasing = n2 > n1
+        break
+
+    for j in range(0, len(report)):
+        if j == len(report) - 1:
+            break
+
+        n1, n2 = report[j], report[j + 1]
+        if n1 == n2:
+            return False
+        if increasing and n1 > n2:
+            return False
+        if not increasing and n1 < n2:
+            return False
+
+        if 1 < abs(n2 - n1) > 3:
+            return False
+
+    return True
+
+
+def count_safe_reports(f: TextIO) -> int:
+    total = 0
+    for report in read_input(f):
+        safe = is_safe(report)
+
+        if safe:
+            total += 1
+
+    return total
+
+
+def count_safe_reports_with_tolerance(f: TextIO) -> int:
+    total = 0
+    for report in read_input(f):
+        safe = is_safe(report)
+
+        if not safe:
+            for n in range(1, len(report)+1):
+                safe = is_safe(report[0:n-1] + report[n:])
+                if safe:
+                    break
+
+        if safe:
+            total += 1
+
+    return total
+
+
+def main():
+    input_file = "input.txt"
+
+    with open(input_file, "r") as f:
+        print(f"safe_reports = {count_safe_reports(f)}")
+
+    with open(input_file, "r") as f:
+        print(f"safe_reports_with_tolerance = {count_safe_reports_with_tolerance(f)}")
+
+
+if __name__ == "__main__":
+    main()

hello.py

@@ -1,6 +0,0 @@
-def main():
-    print("Hello from aoc-2024!")
-
-
-if __name__ == "__main__":
-    main()