From fb4008682185abcc253fc34c314ba5a9e8a12f49 Mon Sep 17 00:00:00 2001
From: Holly McFarland <me@hollymcfarland.com>
Date: Wed, 11 Dec 2024 17:33:54 -0500
Subject: [PATCH] day 7

---
 day_07/part_a.py | 32 ++++++++++++++++++++++++++++++++
 day_07/part_b.py | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 66 insertions(+)
 create mode 100644 day_07/part_a.py
 create mode 100644 day_07/part_b.py

diff --git a/day_07/part_a.py b/day_07/part_a.py
new file mode 100644
index 0000000..5571de9
--- /dev/null
+++ b/day_07/part_a.py
@@ -0,0 +1,32 @@
+import aocd
+
+def get_calibrations(data):
+    for line in data.split('\n'):
+        target, *operands = line.replace(':', '').split()
+        yield int(target), tuple(int(n) for n in operands)
+
+def can_produce_target(target, operands, current=0):
+    # Base case, we're out of numbers to apply
+    if not operands:
+        return target == current
+
+    # We've gone too high
+    if current > target:
+        return False
+    
+    return can_produce_target(target, operands[1:], current + operands[0]) \
+        or can_produce_target(target, operands[1:], current * operands[0])
+
+def solve(data):
+    return sum(target*can_produce_target(target, operands) for target, operands in get_calibrations(data))
+
+if __name__ == '__main__':
+    puz = aocd.models.Puzzle(year=2024, day=7)
+
+    # data = puz.examples[0].input_data
+    data = puz.input_data
+
+    solution = solve(data)
+
+    print(solution)
+    aocd.submit(solution, year=2024, day=7, part='a')
\ No newline at end of file
diff --git a/day_07/part_b.py b/day_07/part_b.py
new file mode 100644
index 0000000..0918147
--- /dev/null
+++ b/day_07/part_b.py
@@ -0,0 +1,34 @@
+import aocd
+import math
+
+def get_calibrations(data):
+    for line in data.split('\n'):
+        target, *operands = line.replace(':', '').split()
+        yield int(target), tuple(int(n) for n in operands)
+
+def can_produce_target(target, operands, current=0):
+    # Base case, we're out of numbers to apply
+    if not operands:
+        return target == current
+
+    # We've gone too high
+    if current > target:
+        return False
+    
+    return can_produce_target(target, operands[1:], current + operands[0]) \
+        or can_produce_target(target, operands[1:], current * operands[0]) \
+        or can_produce_target(target, operands[1:], current * 10**math.floor(math.log(operands[0], 10) + 1) + operands[0])
+
+def solve(data):
+    return sum(target*can_produce_target(target, operands) for target, operands in get_calibrations(data))
+
+if __name__ == '__main__':
+    puz = aocd.models.Puzzle(year=2024, day=7)
+
+    # data = puz.examples[0].input_data
+    data = puz.input_data
+
+    solution = solve(data)
+
+    print(solution)
+    aocd.submit(solution, year=2024, day=7, part='b')
\ No newline at end of file