1 files changed, 40 insertions, 0 deletions
diff --git a/21.py b/21.py
new file mode 100644
index 0000000..a2c0365
--- /dev/null
+++ b/21.py
@@ -0,0 +1,40 @@
+from functools import cache
+from utils import open_day
+
+monkeys = {}
+with open_day(21) as f:
+    for line in f:
+        target, expr = line.rstrip().split(': ')
+        expr = expr.split(' ')
+        if len(expr) == 1:
+            expr = int(expr[0])
+        monkeys[target] = expr
+
+ops = {
+    '+': lambda a, b: a + b,
+    '-': lambda a, b: a - b,
+    '*': lambda a, b: a * b,
+    '/': lambda a, b: a // b,
+}
+
+@cache
+def eval_monkey(m):
+    expr = monkeys[m]
+    if isinstance(expr, int):
+        return expr
+    return ops[expr[1]](eval_monkey(expr[0]), eval_monkey(expr[2]))
+
+print(eval_monkey('root'))
+
+with open('21.z3', 'w') as f:
+    f.write(''.join(f'(declare-const {monkey} Int)\n' for monkey in monkeys.keys()))
+    for k, v in monkeys.items():
+        if k == 'humn': continue
+        if k == 'root':
+            print(f'(assert (= {v[0]} {v[2]}))', file=f)
+            continue
+        if isinstance(v, int):
+            print(f'(assert (= {k} {v}))', file=f)
+        else:
+            print(f'(assert (= {k} ({v[1]} {v[0]} {v[2]})))', file=f)
+    print('(check-sat)\n(get-model)', file=f)