Add solution for day 15

2022/day15/code.py

@@ -0,0 +1,71 @@
+#!/usr/bin/env python3
+
+import sys, re
+from collections import defaultdict
+
+MAP = defaultdict(lambda: defaultdict(lambda: '.'))
+SENSORS = {}
+MINX = 0
+MAXX = 0
+
+def add_sensor(line):
+    groups = re.compile(r"Sensor at x=(?P<sx>-?\d+), y=(?P<sy>-?\d+): closest beacon is at x=(?P<bx>-?\d+), y=(?P<by>-?\d+)").search(line)
+    sx = int(groups.group("sx"))
+    sy = int(groups.group("sy"))
+    bx = int(groups.group("bx"))
+    by = int(groups.group("by"))
+    SENSORS[(sx,sy)] = (bx,by)
+    MAP[sy][sx] = 'S'
+    MAP[by][bx] = 'B'
+
+def cross_out(y):
+    for sx,sy in SENSORS.keys():
+        bx, by = SENSORS[(sx,sy)]
+        global MINX, MAXX
+        d = abs(sx - bx) + abs(sy - by)
+        if bx > MAXX: MAXX = bx
+        if sx + d > MAXX: MAXX = sx + d
+        if bx < MINX: MINX = bx
+        if sx - d < MINX: MINX = sx - d
+        if y in range(sy-d,sy+d+1): 
+            dif = d - abs(sy-y)
+            for x in range(sx-dif,sx+dif):
+                MAP[y][x] = '#'
+
+# for the chsllenge, needs to be called with './code.py input 2000000'
+if __name__ == '__main__':
+    inp = [add_sensor(line.strip('\n')) for line in open(sys.argv[1])]
+    y = int(sys.argv[2])
+    print(SENSORS)
+
+    # challenge 1
+    cross_out(y)
+    no_beacon = 0
+    for x in range(MINX,MAXX+1):
+        if MAP[y][x] == '#': no_beacon += 1
+
+    res1 = str(no_beacon)
+    print("challenge 1:" + "\n" +  res1 + "\n")
+
+    # challenge 2
+    tf = 0
+    for j in range(0,2*y+1):
+        i = 0
+        while i < 2*y+1:
+            b = ''
+            for sx,sy in SENSORS.keys():
+                bx, by = SENSORS[(sx,sy)]
+                d = abs(sx - bx) + abs(sy - by)
+                dy = max(0,d - abs(sx-i))
+                dif = max(0,d - abs(sy-j))
+                if j in range(sy-dy,sy+dy+1) and i in range(sx-dif,sx+dif+1):
+                    b = 'y'
+                    i = sx + dif + 1
+            if b == 'y': continue
+            tf = i*4000000 + j
+            print(i,j,tf)
+            break
+
+    res2 = str(tf)
+    print("challenge 2:" + "\n" +  res2 + "\n")
+