Solve day 9 till 11 and part 1 day 12 2018

2018/d11.py

@@ -0,0 +1,80 @@
+from functools import lru_cache
+
+
+@lru_cache
+def score(serial, x, y):
+    # Find the fuel cell's rack ID, which is its X coordinate plus 10.
+    # Begin with a power level of the rack ID times the Y coordinate.
+    # Increase the power level by the value of the grid serial number (your puzzle input).
+    # Set the power level to itself multiplied by the rack ID.
+    # Keep only the hundreds digit of the power level (so 12345 becomes 3; numbers with no hundreds digit become 0).
+    # Subtract 5 from the power level.
+    rack_id = x + 10
+    power_level = rack_id * y
+    power_level += serial
+    power_level *= rack_id
+    try:
+        return int(str(power_level)[-3]) - 5
+    except IndexError:
+        return -5
+
+
+def part_1(data):
+    v = int(data.strip())
+    max_val = 0
+    max_coord = None
+
+    assert score(8, 3, 5) == 4
+    assert score(57, 122, 79) == -5
+    assert score(39, 217, 196) == 0
+
+    for x in range(1, 299):
+        for y in range(1, 299):
+            s = 0
+            for x2 in range(x, x + 3):
+                for y2 in range(y, y + 3):
+                    s += score(v, x2, y2)
+                    if x2 > 300 or y2 > 300:
+                        assert False
+            if s > max_val:
+                max_val = s
+                max_coord = (x, y)
+    assert max_coord is not None
+    print(",".join(list(map(str, max_coord))))
+
+
+def part_2(data):
+    v = int(data.strip())
+    max_val = 0
+    max_coord = None
+
+    # brute force, just tried if 15 is small enough
+    for size in range(2, 15):
+        for x in range(1, 299):
+            for y in range(1, 299):
+                s = 0
+                if x + size > 300 or y + size > 300:
+                    break
+
+                for x2 in range(x, x + size):
+                    for y2 in range(y, y + size):
+                        s += score(v, x2, y2)
+                        if x2 > 300 or y2 > 300:
+                            assert False
+                if s > max_val:
+                    max_val = s
+                    max_coord = (x, y, size)
+    assert max_coord is not None
+    print(",".join(list(map(str, max_coord))))
+
+
+def main():
+    input_file = __file__.replace(".py", ".txt")
+    with open(input_file) as f:
+        data = f.read()
+    part_1(data)
+    part_2(data)
+
+
+if __name__ == "__main__":
+    main()