Add day-02

Author: Mishco

2025/day-02/main.py

@@ -2,11 +2,59 @@
 
 
 def part1():
-    pass
+    lines = """
+    11-22,95-115,998-1012,1188511880-1188511890,222220-222224,
+    1698522-1698528,446443-446449,38593856-38593862,565653-565659,
+    824824821-824824827,2121212118-2121212124
+    """
+    lines =open('../inputs/day-02.txt', 'r').read().strip()
+    # lines
+    invalid_ids = []
+    ranges = [r.strip() for r in lines.split(",") if r.strip()]
+    for r in ranges:
+        start_str, end_str = r.split("-")
+        start = int(start_str)
+        end = int(end_str)
+        for i in range(start, end + 1):
+            s = str(i)
+            if len(s) % 2 == 0:
+                half = len(s) // 2
+                if s[:half] == s[half:]:
+                    invalid_ids.append(i)
 
+    # print(f"Part 1: {len(invalid_ids)} invalid IDs")
+    # print(f"Invalid IDs: {invalid_ids}")
+    print(sum(invalid_ids))
+
+def is_repeated_substring(substr: str) -> bool:
+    n = len(substr)
+    for l in range(1, n // 2 + 1):
+        if n % l == 0 and substr == substr[:l] * (n // l):
+            return True
+    return False
 
 def part2():
-    pass
+    lines = """
+        11-22,95-115,998-1012,1188511880-1188511890,222220-222224,
+        1698522-1698528,446443-446449,38593856-38593862,565653-565659,
+        824824821-824824827,2121212118-2121212124
+        """
+    lines = open('../inputs/day-02.txt', 'r').read().strip()    # lines
+    invalid_any = []
+    ranges = [r.strip() for r in lines.split(",") if r.strip()]
+    for r in ranges:
+        start_str, end_str = r.split("-")
+        start = int(start_str)
+        end = int(end_str)
+        for i in range(start, end + 1):
+            substring = str(i)
+            if is_repeated_substring(substring):
+                invalid_any.append(i)
+
+    # print(f"Part 2: {len(invalid_any)} invalid IDs")
+    # print(f"Invalid IDs: {invalid_any}")
+    print(sum(invalid_any))
+
 
 
 if __name__ == "__main__":