✅ Adding Day 15 OG & One-line Solutions!

Author: savbell

Diff for: 2023/day-15.py

@@ -0,0 +1,66 @@
+'''
+2023 Advent of Code - Day 15 (https://adventofcode.com/2023/day/15)
+Solution by Sav Bell (https://github.com/savbell)
+Challenge: Solve every day in a single line of Python code.
+           See full progress at https://github.com/savbell/advent-of-code-one-liners
+'''
+
+# Input files not included in repo per copyright & Eric Wastl's request.
+# https://www.reddit.com/r/adventofcode/wiki/faqs/copyright/inputs/
+# Replace with path to your personal input file if you would like to run the code.
+input_file = '2023/day-15.txt'
+
+# To match the format of input files for the Basilisk.
+q = { 15: open(input_file).read().strip() }
+
+
+######################### PART 1: MULTI-LINE SOLUTION #########################
+steps = q[15].split(',')
+values = []
+for s in steps:
+    value = 0
+    for c in s:
+        value += ord(c)
+        value *= 17
+        value %= 256
+    values.append(value)
+
+print('Day 15 Part 1:',sum(values))
+
+########################## PART 1: ONE-LINE SOLUTION ##########################
+print('Day 15 Part 1:',sum([(v:=0) or [v:=(v+ord(c))*17%256 for c in s] and v for s in q[15].split(',')]))
+
+
+######################## PART 2: MULTI-LINE SOLUTION ##########################
+steps = q[15].split(',')
+boxes = [[] for _ in range(256)]
+for s in steps:
+    label = ''.join([c for c in s if c.isalpha()])
+    operation = ''.join([c for c in s if not c.isalnum()])
+    focal = ''.join([c for c in s if c.isdigit()])
+    lens = (label, focal)
+    box = 0
+    for c in label:
+        box += ord(c)
+        box *= 17
+        box %= 256
+    if operation == '=':
+        if label not in [x[0] for x in boxes[box]]:
+            boxes[box].append(lens)
+        else:
+            index = [x[0] for x in boxes[box]].index(label)
+            boxes[box].pop(index)
+            boxes[box].insert(index, lens)
+    elif operation == '-':
+        if label in [x[0] for x in boxes[box]]:
+            boxes[box].pop([x[0] for x in boxes[box]].index(label))
+
+score = 0
+for i,box in enumerate(boxes):
+    for j,lens in enumerate(box):
+        score += (i+1)*(j+1)*int(lens[1])
+        
+print('Day 15 Part 2:',score)
+
+########################## PART 2: ONE-LINE SOLUTION ##########################
+print('Day 15 Part 2:',sum((b:=[[] for _ in range(256)]) and [((l:=''.join([c for c in s if c.isalpha()])) and (o:=''.join([c for c in s if not c.isalnum()])) and (f:=''.join([c for c in s if c.isdigit()])) and (d:=(l,f)) and (a:=0) or 1) and not (a:=0) and [a:=(a+ord(c))*17%256 for c in l] and ((b[a].append(d) if l not in [x[0] for x in b[a]] else ((e:=[x[0] for x in b[a]].index(l)) or 1) and b[a].pop(e) and b[a].insert(e,d)) if o=='=' else b[a].pop([x[0] for x in b[a]].index(l)) if l in [x[0] for x in b[a]] else 0) for s in q[15].split(',')] and [(i+1)*(j+1)*int(n[1]) for i,p in enumerate(b) for j,n in enumerate(p)]))