Round 3

Author: MasterCoolDude

rounds/3_dna/solution.py

@@ -5,13 +5,46 @@
 own faster implementation.
 """
 
+from concurrent.futures import ThreadPoolExecutor
+from itertools import repeat
 from .baseline import find_matches as _baseline
 
 
+def _process_record(record: str, pattern_str: str) -> tuple[str, list[int]] | None:
+    if not record.strip():
+        return None
+
+    lines = record.split("\n")
+    record_id = lines[0].strip()
+    sequence = "".join(lines[1:]).replace(" ", "")
+
+    positions: list[int] = []
+    start = 0
+    while True:
+        pos = sequence.find(pattern_str, start)
+        if pos == -1:
+            break
+        positions.append(pos)
+        start = pos + 1
+
+    if positions:
+        return (record_id, positions)
+    return None
+
+
 def find_matches(fasta_path: str, pattern: bytes) -> list[tuple[str, list[int]]]:
-    """Find every FASTA record whose sequence contains ``pattern``.
 
-    Returns ``[(record_id, [positions...]), ...]`` in file order.
-    """
-    # TODO: remove this delegation and write your own implementation here.
-    return _baseline(fasta_path, pattern)
+    pattern_str = pattern.decode("ascii")
+    with open(fasta_path, "r") as f:
+        text = f.read()
+
+    records = [record for record in text.split(">") if record.strip()]
+    matches: list[tuple[str, list[int]]] = []
+
+    with ThreadPoolExecutor(max_workers=16) as executor:
+        for result in executor.map(_process_record, records, repeat(pattern_str)):
+            if result:
+                matches.append(result)
+
+    return matches
+