day 14 part 1

2024/Makefile

@@ -6,7 +6,7 @@
 # Then:
 #   make DAY=1 DEBUG=0
 
-DAY ?= 9
+DAY ?= 14
 DEBUG ?= 1
 
 SAMPLE = day$(DAY)/sample.txt

2024/README.md

@@ -3,7 +3,7 @@
 I've been blogging about my solutions.
 Start with Day 1) here: https://www.perrotta.dev/2024/12/advent-of-code-2024-day-1/
 
-![Completion Status](https://img.shields.io/badge/stars%20⭐-18/50-yellow)
+![Completion Status](https://img.shields.io/badge/stars%20⭐-19/50-yellow)
 
 The Chief Historian is always present for the big Christmas sleigh launch, but nobody has seen him in months! Last anyone heard, he was visiting locations that are historically significant to the North Pole; a group of Senior Historians has asked you to accompany them as they check the places they think he was most likely to visit.
 

2024/day17/input.txt

@@ -0,0 +1,5 @@
+Register A: 37293246
+Register B: 0
+Register C: 0
+
+Program: 2,4,1,6,7,5,4,4,1,7,0,3,5,5,3,0

2024/day17/main.py

@@ -0,0 +1,70 @@
+#!/usr/bin/env python3
+import sys
+
+
+def main():
+    with open(sys.argv[1]) as input:
+        lines = input.read().splitlines()
+
+    a, b, c = [int(line.split()[2]) for line in lines[0:3]]
+    program = [int(op) for op in lines[4].split()[1].split(",")]
+    ip = 0
+    stdout = []
+
+    def combo(operand):
+        assert 0 <= operand < 7
+
+        if 0 <= operand <= 3:
+            return operand
+        elif operand == 4:
+            return a
+        elif operand == 5:
+            return b
+        elif operand == 6:
+            return c
+
+    while ip < len(program) - 1:
+        opcode = program[ip]
+        operand = program[ip + 1]
+
+        # adv, division
+        if opcode == 0:
+            numerator = a
+            denominator = 2 ** combo(operand)
+            a = numerator // denominator
+        # bxl, bitwise xor
+        elif opcode == 1:
+            b ^= operand
+        # bst, modulo
+        elif opcode == 2:
+            b = combo(operand) % 8
+        # jnz
+        elif opcode == 3:
+            if a != 0:
+                ip = operand
+                continue
+        # bxc, bitwise xor
+        elif opcode == 4:
+            b ^= c
+        # out
+        elif opcode == 5:
+            stdout.append(combo(operand) % 8)
+        # bdv
+        elif opcode == 6:
+            numerator = a
+            denominator = 2 ** combo(operand)
+            b = numerator // denominator
+        # cdv
+        elif opcode == 7:
+            numerator = a
+            denominator = 2 ** combo(operand)
+            c = numerator // denominator
+
+        ip += 2
+
+    # part one
+    print(",".join(map(str, stdout)))
+
+
+if __name__ == '__main__':
+    main()

2024/day17/output.txt

@@ -0,0 +1 @@
+1,5,0,1,7,4,1,0,3

2024/day17/sample.txt

@@ -0,0 +1,5 @@
+Register A: 729
+Register B: 0
+Register C: 0
+
+Program: 0,1,5,4,3,0