2 files changed, 62 insertions, 5 deletions
diff --git a/19/py/d23.py b/19/py/d23.py
new file mode 100644
index 0000000..14416e9
--- /dev/null
+++ b/19/py/d23.py
@@ -0,0 +1,54 @@
+import collections
+import intcode
+import sys
+
+program = [int(x) for x in open("../input/23", "r").readline().split(",")]
+
+computers = [intcode.Computer(program, network_id=i) for i in range(50)]
+queues = [collections.deque([i]) for i in range(len(computers))]
+output_buffers = [[] for _ in range(len(computers))]
+waiting = [False for _ in range(len(computers))]
+
+prev_nat_x, prev_nat_y = -1, -1
+nat_x, nat_y = 0, 0
+
+while True:
+    for i in range(len(computers)):
+        c = computers[i]
+        c.step()
+        if c.SIG_INPUT:
+            if len(queues[i]) > 0:
+                c.input = queues[i].popleft()
+                waiting[i] = False
+            else:
+                c.input = -1
+                waiting[i] = True
+        if c.SIG_OUTPUT:
+            output_buffers[i].append(c.output)
+            c.output = None
+            waiting[i] = False
+            if len(output_buffers[i]) == 3:
+                addr, x, y = output_buffers[i]
+                output_buffers[i] = []
+                if addr == 255:
+                    nat_x, nat_y = x, y
+                else:
+                    queues[addr].append(x)
+                    queues[addr].append(y)
+    empty_queues = True
+    for q in queues:
+        if len(q) > 0:
+            empty_queues = False
+            break
+    all_waiting = True
+    for w in waiting:
+        if not w:
+            all_waiting = False
+            break
+    if empty_queues and all_waiting:
+        queues[0].append(nat_x)
+        queues[0].append(nat_y)
+        if nat_y == prev_nat_y:
+            print(nat_y)
+            sys.exit()
+        prev_nat_x, prev_nat_y = nat_x, nat_y
diff --git a/19/py/intcode.py b/19/py/intcode.py
index 843688c..1c0f062 100644
--- a/19/py/intcode.py
+++ b/19/py/intcode.py
@@ -13,14 +13,17 @@ BAS = 9
 HAL = 99
 
 class Computer(object):
-    def __init__(self, program, ascii=False):
+    def __init__(self, program, ascii=False, network_id=None):
         self.program = program
         self.memory_size = len(self.program)
         self.instruction_cache = {}
-        if ascii:
-            self.SIG_ASCII = True
-        else:
-            self.SIG_ASCII = False
+
+        self.SIG_ASCII = ascii
+
+        self.SIG_NET = False
+        if network_id is not None:
+            self.SIG_NET = True
+            self.network_id = network_id
 
         self.reset()