Messy day 18

18.py

@@ -0,0 +1,113 @@
+from collections import defaultdict
+
+get_value = lambda registers, operand: registers[operand] if operand in registers else int(operand)
+
+def handle_snd(pc, registers, state, args):
+    state['snd'].append(get_value(registers, args[0]))
+    state['sndc'] += 1
+    return pc + 1
+
+def handle_set(pc, registers, state, args):
+    registers[args[0]] = get_value(registers, args[1])
+    return pc + 1
+
+def handle_add(pc, registers, state, args):
+    registers[args[0]] += get_value(registers, args[1])
+    return pc + 1
+
+def handle_mul(pc, registers, state, args):
+    registers[args[0]] *= get_value(registers, args[1])
+    return pc + 1
+
+def handle_mod(pc, registers, state, args):
+    registers[args[0]] %= get_value(registers, args[1])
+    return pc + 1
+
+def handle_jgz(pc, registers, state, args):
+    return pc + get_value(registers, args[1]) if get_value(registers, args[0]) > 0 else pc + 1
+
+def handle_rcv_p1(pc, registers, state, args):
+    if get_value(registers, args[0]) != 0:
+        state['recovered'].append(state['snd'][-1])
+    return pc + 1
+
+def handle_rcv_p2(pc, registers, state, args):
+    if len(state['rcv']) > 0:
+        registers[args[0]] = state['rcv'].pop(0)
+        return pc + 1
+    else:
+        return pc
+
+def process_p1(instructions):
+    pc, state, registers = 0, {'snd': [], 'sndc': 0, 'recovered': []}, defaultdict(lambda: 0)
+    ops = {
+        'snd': handle_snd,
+        'set': handle_set,
+        'add': handle_add,
+        'mul': handle_mul,
+        'mod': handle_mod,
+        'jgz': handle_jgz,
+        'rcv': handle_rcv_p1,
+    }
+    while len(state['recovered']) == 0:
+        ins = instructions[pc]
+        pc = ops[ins[0]](pc, registers, state, ins[1:])
+    return state['recovered'][0]
+
+
+def can_execute(programs):
+    for p in programs:
+        if p['state']['terminated']:
+            yield False
+        elif p['state']['waiting'] and len(p['state']['rcv']) == 0:
+            yield False
+        else:
+            yield True
+
+
+def process_p2(instructions):
+    p1_to_p2, p2_to_p1 = [], []
+    programs = [{
+        'pc': 0,
+        'state': {'snd': p1_to_p2, 'sndc': 0, 'rcv': p2_to_p1, 'terminated': False, 'waiting': False},
+        'regs': defaultdict(lambda: 0)
+    }, {
+        'pc': 0,
+        'state': {'snd': p2_to_p1, 'sndc': 0, 'rcv': p1_to_p2, 'terminated': False, 'waiting': False},
+        'regs': defaultdict(lambda: 0),
+    }]
+    programs[1]['regs']['p'] = 1
+
+    ops = {
+        'snd': handle_snd,
+        'set': handle_set,
+        'add': handle_add,
+        'mul': handle_mul,
+        'mod': handle_mod,
+        'jgz': handle_jgz,
+        'rcv': handle_rcv_p2,
+    }
+
+    p = 0
+    while any(can_execute(programs)):
+        for _ in range(1000):
+            pc = programs[p]['pc']
+            programs[p]['state']['waiting'] = False
+            if pc < 0 or pc >= len(instructions):
+                programs[p]['state']['terminated'] = True
+                break
+            ins = instructions[pc]
+            programs[p]['pc'] = ops[ins[0]](pc, programs[p]['regs'], programs[p]['state'], ins[1:])
+            if programs[p]['pc'] == pc:
+                programs[p]['state']['waiting'] = True
+                break
+        p = 1 - p
+
+    return programs[1]['state']['sndc']
+
+
+
+with open('data/18.txt', 'r') as file:
+    input = list(map(str.split, file.readlines()))
+    print(f'Part one: {process_p1(input)}')
+    print(f'Part two: {process_p2(input)}')

data/18.txt

@@ -0,0 +1,41 @@
+set i 31
+set a 1
+mul p 17
+jgz p p
+mul a 2
+add i -1
+jgz i -2
+add a -1
+set i 127
+set p 680
+mul p 8505
+mod p a
+mul p 129749
+add p 12345
+mod p a
+set b p
+mod b 10000
+snd b
+add i -1
+jgz i -9
+jgz a 3
+rcv b
+jgz b -1
+set f 0
+set i 126
+rcv a
+rcv b
+set p a
+mul p -1
+add p b
+jgz p 4
+snd a
+set a b
+jgz 1 3
+snd b
+set f 1
+add i -1
+jgz i -11
+snd a
+jgz f -16
+jgz a -19