2024.04

challenges/2024/04-ceresSearch/main.py

@@ -0,0 +1,81 @@
+import sys
+import gridutil.grid as grid
+import gridutil.coord as coord
+
+
+def parse(instr: str) -> grid.Grid:
+    return grid.parse(instr.upper())
+
+
+def one(instr: str):
+    wordsearch = parse(instr)
+
+    seq_starts = list(
+        map(lambda x: x[0], filter(lambda x: x[1] == "X", wordsearch.items()))
+    )
+    detected_sequences = set()
+
+    for start_pos in seq_starts:
+        for xdir in [-1, 0, 1]:
+            for ydir in [-1, 0, 1]:
+
+                if xdir == 0 and ydir == 0:
+                    continue
+
+                delta = coord.Coordinate(xdir, ydir)
+
+                ok = True
+                for i, v in enumerate("XMAS"):
+                    if not ok:
+                        break
+
+                    g = wordsearch.get(coord.add(start_pos, coord.mult(delta, i)), "-")
+                    ok = g == v
+
+                if ok:
+                    detected_sequences.add((start_pos, delta))
+
+    return len(detected_sequences)
+
+
+def check_cross_adjacents(s: str) -> bool:
+    return s == "SM" or s == "MS"
+
+
+def two(instr: str):
+    wordsearch = parse(instr)
+
+    seq_starts = list(
+        map(lambda x: x[0], filter(lambda x: x[1] == "A", wordsearch.items()))
+    )
+    detected_sequences = set()
+
+    for start_pos in seq_starts:
+
+        a = wordsearch.get(coord.add(start_pos, (-1, -1)), "") + wordsearch.get(
+            coord.add(start_pos, (1, 1)), ""
+        )
+        b = wordsearch.get(coord.add(start_pos, (-1, 1)), "") + wordsearch.get(
+            coord.add(start_pos, (1, -1)), ""
+        )
+
+        if check_cross_adjacents(a) and check_cross_adjacents(b):
+            detected_sequences.add(start_pos)
+
+    return len(detected_sequences)
+
+
+def _debug(*args, **kwargs):
+    kwargs["file"] = sys.stderr
+    print(*args, **kwargs)
+
+
+if __name__ == "__main__":
+    if len(sys.argv) < 2 or sys.argv[1] not in ["1", "2"]:
+        print("Missing day argument", file=sys.stderr)
+        sys.exit(1)
+    inp = sys.stdin.read().strip()
+    if sys.argv[1] == "1":
+        print(one(inp))
+    else:
+        print(two(inp))