finish day2.1, move input reading out of day1

day1/report_repair.py

@@ -1,8 +1,9 @@
-import pytest
 from itertools import combinations
 from typing import Tuple, List
 from math import prod
 
+from utils import read_input_data
+
 
 def test_find_sum_two():
     test_string = """
@@ -27,12 +28,6 @@ def test_find_sum_three():
     assert find_sum(intify_input(test_string), 3) == (979, 366, 675)
 
 
-def read_input_data(path: str) -> str:
-    with open(path, 'r') as f:
-        data = f.read()
-    return data
-
-
 def find_sum(data: List[int], n_summands: int = 2, target: int = 2020) -> Tuple[int, int]:
     for combo in combinations(data, n_summands):
         if sum(combo) == target:

day2/password_philosophy.py

@@ -0,0 +1,80 @@
+from utils import read_input_data
+from collections import Counter
+from typing import List, Dict, Tuple
+
+
+class TestClass:
+    test_data = """1-3 a: abcde
+1-3 b: cdefg
+2-9 c: ccccccccc
+"""
+    
+    def test_count_valid_passwords(self):
+        parsed = parse_input_data(self.test_data)
+        assert count_valid_passwords(parsed) == 2
+
+    def test_parse_input_data(self):
+        parsed = parse_input_data(self.test_data)
+        assert parsed == [
+            (
+                {
+                    'lower_bound': 1,
+                    'upper_bound': 3,
+                    'char': 'a',
+                },
+                'abcde'
+            ),
+            (
+                {
+                    'lower_bound': 1,
+                    'upper_bound': 3,
+                    'char': 'b',
+                },
+                'cdefg'
+            ),
+            (
+                {
+                    'lower_bound': 2,
+                    'upper_bound': 9,
+                    'char': 'c',
+                },
+                'ccccccccc'
+            ),
+        ]
+
+
+def parse_input_data(data: str) -> List[Tuple[Dict, str]]:
+    lines = [line for line in data.split('\n') if line]
+    parsed_passwords = []
+    for line in lines:
+        policy, password = line.split(':')
+        password = password.strip()
+        policy_dict = parse_policy(policy)
+        parsed_passwords.append((policy_dict, password))
+    return parsed_passwords
+
+
+def parse_policy(input_string: str) -> Dict[str, int]:
+    range, char = input_string.split()
+    lower_bound, upper_bound = range.split('-')
+    return {
+        'upper_bound': int(upper_bound),
+        'lower_bound': int(lower_bound),
+        'char': char,
+    }
+
+
+def verify_password(policy, password) -> bool:
+    counter = Counter(password)
+    return policy['lower_bound'] <= counter[policy['char']] <= policy['upper_bound']
+
+
+def count_valid_passwords(parsed_passwords: List[Tuple[Dict, str]]):
+    return sum([verify_password(pol, pwd) for pol, pwd in parsed_passwords])
+
+
+if __name__ == '__main__':
+    raw_data = read_input_data('input.txt')
+    parsed_data = parse_input_data(raw_data)
+    result = count_valid_passwords(parsed_data)
+    print(f'There are {result} valid Passwords, according to their policies')

utils.py

@@ -0,0 +1,4 @@
+def read_input_data(path: str) -> str:
+    with open(path, 'r') as f:
+        data = f.read()
+    return data