Do day 6.

d6.py

@@ -0,0 +1,41 @@
+import re
+from string import ascii_lowercase, ascii_uppercase
+
+EXAMPLE = """
+mjqjpqmgbljsphdztnvjfqwrcgsmlb
+"""
+
+def clean(text: str) -> list[str]:
+    return list(filter(lambda l: l.strip() != "", text.splitlines()))
+
+def solve(lines: list[str]):
+    line = lines[0]
+    for i in range(len(lines[0])):
+        l = line[i:i + 4]
+        if len(set(l)) == len(l):
+            return i + 4
+    # 2:55
+
+def solve2(lines: list[str]):
+    line = lines[0]
+    for i in range(len(lines[0])):
+        l = line[i:i + 14]
+        if len(set(l)) == len(l):
+            return i + 14
+    # 3:50
+
+def main():
+    example = clean(EXAMPLE)
+    print("Example  1:", solve(example))
+
+    data = clean(open("i6.txt").read())
+    print("Solution 1:", solve(data))
+
+    example = clean(EXAMPLE)
+    print("Example  2:", solve2(example))
+
+    data = clean(open("i6.txt").read())
+    print("Solution 2:", solve2(data))
+
+if __name__ == "__main__":
+    main()