From 0b53406b52204a9a7f0f1130a0b862d82f9e1fa2 Mon Sep 17 00:00:00 2001
From: Mikael CAPELLE <capelle.mikael@gmail.com>
Date: Thu, 15 Dec 2022 09:36:19 +0100
Subject: [PATCH] Add day 15.

---
 2022/day15.py         | 51 +++++++++++++++++++++++++++++++++++++++++++
 2022/inputs/day15.txt | 30 +++++++++++++++++++++++++
 2 files changed, 81 insertions(+)
 create mode 100644 2022/day15.py
 create mode 100644 2022/inputs/day15.txt

diff --git a/2022/day15.py b/2022/day15.py
new file mode 100644
index 0000000..f2c141c
--- /dev/null
+++ b/2022/day15.py
@@ -0,0 +1,51 @@
+# -*- encoding: utf-8 -*-
+
+import sys
+
+import numpy as np
+import parse
+from docplex.mp.model import Model
+
+lines = sys.stdin.read().splitlines()
+
+sensor_to_beacon: dict[tuple[int, int], tuple[int, int]] = {}
+
+for line in lines:
+    r = parse.parse(
+        "Sensor at x={sx}, y={sy}: closest beacon is at x={bx}, y={by}", line
+    )
+    sensor_to_beacon[int(r["sx"]), int(r["sy"])] = (int(r["bx"]), int(r["by"]))
+
+xy_max = 4_000_000 if max(sensor_to_beacon) > (1_000, 0) else 20
+row = 2_000_000 if max(sensor_to_beacon) > (1_000, 0) else 10
+
+no_beacons_row_l: list[np.ndarray] = []
+
+for (sx, sy), (bx, by) in sensor_to_beacon.items():
+    d = abs(sx - bx) + abs(sy - by)  # closest
+
+    no_beacons_row_l.append(sx - np.arange(0, d - abs(sy - row) + 1))
+    no_beacons_row_l.append(sx + np.arange(0, d - abs(sy - row) + 1))
+
+beacons_at_row = set(bx for (bx, by) in sensor_to_beacon.values() if by == row)
+no_beacons_row = set(np.concatenate(no_beacons_row_l)).difference(beacons_at_row)
+
+print(f"answer 1 is {len(no_beacons_row)}")
+
+# === part 2 ===
+
+m = Model()
+
+x, y = m.continuous_var_list(2, ub=xy_max, name=["x", "y"])
+
+for (sx, sy), (bx, by) in sensor_to_beacon.items():
+    d = abs(sx - bx) + abs(sy - by)
+    m.add_constraint(m.abs(x - sx) + m.abs(y - sy) >= d + 1, ctname=f"ct_{sx}_{sy}")
+
+m.set_objective("min", x + y)
+
+s = m.solve()
+
+# 10621647166538
+answer_2 = 4_000_000 * int(s.get_value(x)) + int(s.get_value(y))
+print(f"answer 2 is {answer_2}")
diff --git a/2022/inputs/day15.txt b/2022/inputs/day15.txt
new file mode 100644
index 0000000..81d039a
--- /dev/null
+++ b/2022/inputs/day15.txt
@@ -0,0 +1,30 @@
+Sensor at x=2332081, y=2640840: closest beacon is at x=2094728, y=2887414
+Sensor at x=3048293, y=3598671: closest beacon is at x=3872908, y=3598272
+Sensor at x=2574256, y=3973583: closest beacon is at x=2520711, y=4005929
+Sensor at x=3011471, y=2514567: closest beacon is at x=2999559, y=2558817
+Sensor at x=3718881, y=2593817: closest beacon is at x=2999559, y=2558817
+Sensor at x=2388052, y=2201955: closest beacon is at x=2163809, y=1961540
+Sensor at x=3783125, y=3897169: closest beacon is at x=3872908, y=3598272
+Sensor at x=1864613, y=3918152: closest beacon is at x=2520711, y=4005929
+Sensor at x=2850099, y=689863: closest beacon is at x=3231146, y=2000000
+Sensor at x=3431652, y=2328669: closest beacon is at x=3231146, y=2000000
+Sensor at x=3480248, y=3999492: closest beacon is at x=3872908, y=3598272
+Sensor at x=455409, y=3347614: closest beacon is at x=-399822, y=4026621
+Sensor at x=2451938, y=2950107: closest beacon is at x=2094728, y=2887414
+Sensor at x=1917790, y=3194437: closest beacon is at x=2094728, y=2887414
+Sensor at x=3947393, y=3625984: closest beacon is at x=3872908, y=3598272
+Sensor at x=1615064, y=2655330: closest beacon is at x=2094728, y=2887414
+Sensor at x=3630338, y=1977851: closest beacon is at x=3231146, y=2000000
+Sensor at x=3878266, y=3019867: closest beacon is at x=3872908, y=3598272
+Sensor at x=2837803, y=2395749: closest beacon is at x=2999559, y=2558817
+Sensor at x=3979396, y=3697962: closest beacon is at x=3872908, y=3598272
+Sensor at x=109399, y=250528: closest beacon is at x=929496, y=-688981
+Sensor at x=2401381, y=3518884: closest beacon is at x=2520711, y=4005929
+Sensor at x=3962391, y=71053: closest beacon is at x=5368730, y=-488735
+Sensor at x=1751119, y=97658: closest beacon is at x=929496, y=-688981
+Sensor at x=2932155, y=2967347: closest beacon is at x=2999559, y=2558817
+Sensor at x=3326630, y=2845463: closest beacon is at x=2999559, y=2558817
+Sensor at x=3959042, y=1734156: closest beacon is at x=3231146, y=2000000
+Sensor at x=675279, y=1463916: closest beacon is at x=2163809, y=1961540
+Sensor at x=3989603, y=3500749: closest beacon is at x=3872908, y=3598272
+Sensor at x=1963470, y=2288355: closest beacon is at x=2163809, y=1961540