From f97b0b70df17edcab8dcbfe7fe8cf5e4cb3a1fab Mon Sep 17 00:00:00 2001
From: augustin64 <me.git@augustin64.fr>
Date: Wed, 20 Dec 2023 07:06:55 +0100
Subject: [PATCH] Add 2023 day 20

---
 2023/day20.py | 157 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 157 insertions(+)
 create mode 100755 2023/day20.py

diff --git a/2023/day20.py b/2023/day20.py
new file mode 100755
index 0000000..234a8f3
--- /dev/null
+++ b/2023/day20.py
@@ -0,0 +1,157 @@
+#!/usr/bin/python3
+"""
+Jour 20 du défi Advent Of Code pour l'année 2023
+"""
+import os
+import heapq
+import math
+
+FLIP_FLOP=0
+BROADCAST=1
+CONJUNCTION=2
+
+class Module:
+    def __init__(self, text, inputs = None):
+        self.status = {}
+        self.dest = text.split(" -> ")[1].strip().split(", ")
+        if inputs is not None:
+            self.inputs = inputs
+        else:
+            self.inputs = []
+
+        match (text[0]):
+            case '%':
+                self.type = FLIP_FLOP
+                self.status["flip-flopped"] = False
+            case '&':
+                self.type = CONJUNCTION
+                self.status["received"] = {i: "-low" for i in self.inputs}
+            case 'b':
+                self.type = BROADCAST
+
+        if self.type == BROADCAST:
+            self.name = "broadcaster"
+        else:
+            self.name = text.split(" -> ")[0][1:]
+        
+
+    def __repr__(self):
+        if self.type == BROADCAST:
+            return f"{self.name} -> {''.join(self.dest)}"
+        if self.type == CONJUNCTION:
+            return f"&{self.name} -> {''.join(self.dest)} [{self.status['received']}]"
+        if self.type == FLIP_FLOP:
+            return f"%{self.name} -> {''.join(self.dest)}"
+        raise NotImplementedError
+
+
+    def get_signals(self, signal):
+        if self.type == FLIP_FLOP:
+            if signal[1] == "-high":
+                return []
+            if self.status["flip-flopped"]: # Is on ?
+                next = "-low"
+            else:
+                next = "-high"
+            self.status["flip-flopped"] = not self.status["flip-flopped"]
+            return [(dest, next) for dest in self.dest]
+
+        if self.type == CONJUNCTION:
+            self.status["received"][signal[2]] = signal[1]
+            #print({i for i in self.status["received"].values()}, self.status["received"])
+            if "-low" not in {i for i in self.status["received"].values()}:
+                return [(dest, "-low") for dest in self.dest]
+            return [(dest, "-high") for dest in self.dest]
+
+        if self.type == BROADCAST:
+            return [(dest, signal[1]) for dest in self.dest]
+
+        raise NotImplementedError
+                
+
+
+
+def read_sample():
+    """récupère les entrées depuis le fichier texte correspondant"""
+    filename = os.path.join(os.path.dirname(__file__ ), "inputs", "day20.txt")
+    with open(filename, 'r') as f:
+        sample = f.read().split('\n')
+    sample = [ i for i in sample if i != '' ]
+    return sample
+
+def propagate(modules, signal=("broadcaster", "-low")):
+    low_pulses, high_pulses = 0, 0
+    priority_queue = [(0, (signal[0], signal[1], "button"))]
+    while priority_queue:
+        dist, signal = heapq.heappop(priority_queue)
+        if signal[1] == "-low":
+            low_pulses += 1
+        else:
+            high_pulses += 1
+
+        if signal[0] in modules.keys():
+            next_messages = modules[signal[0]].get_signals(signal)
+            for message in next_messages:
+                #print(f"{signal[0]} received {signal[1]}: {message[1]} -> {message[0]}")
+                msg = (message[0], message[1], signal[0])
+                heapq.heappush(priority_queue, (dist+1, msg))
+        elif signal[1] == "-low":
+            return low_pulses, high_pulses, True
+
+    return low_pulses, high_pulses, False
+
+
+def get_modules(sample):
+    modules = { i.name: Module(i) for i in sample }
+
+    for m in modules.values():
+        for d in m.dest:
+            if d in modules.keys():
+                modules[d].inputs.append(m.name)
+                if modules[d].type == CONJUNCTION:
+                    modules[d].status["received"][m.name] = "-low"
+    return modules
+
+
+def part1(sample, times=1000):
+    """Partie 1 du défi"""
+    modules = get_modules(sample)
+
+    #print(modules)
+    somme = (0, 0)
+    for i in range(times):
+        res = propagate(modules)
+        somme = (somme[0]+res[0], somme[1]+res[1])
+    return somme[0]*somme[1], somme
+
+
+def part2(sample):
+    """Partie 1 du défi"""
+    modules = get_modules(sample)
+
+    min_high = {}
+    pre = [m for m in modules if "rx" in m.dest][0]
+    for key in pre.status["received"].keys():
+        min_high[key] = -1
+            
+    #print(modules)
+    activations = 0
+    while True:
+        activations+=1
+        res = propagate(modules)
+        pre = [m for m in modules if "rx" in m.dest][0]
+        for key in pre.status["received"].keys():
+            if pre.status["received"]["key"] == "-high" and min_high[key] == -1:
+                min_high[key] = activations
+
+        if -1 not in min_high.values():
+            return math.lcm(*min_high.values())
+
+
+def main():
+    """Fonction principale"""
+    print(f"part1: {part1(read_sample())}")
+    print(f"part2: {part2(read_sample())}")
+
+if __name__ == "__main__":
+    main()
\ No newline at end of file