Add 2023/20 py

Author: erikw

.devcontainer/devcontainer.json

@@ -5,6 +5,7 @@
 			"packages": [
 				"cloc",
 				"direnv",
+				"graphviz",
 				"multitime",
 				"octave",
 				"shellcheck",

.vscode/settings.json

@@ -30,6 +30,7 @@
         "npos",
         "nprev",
         "pdir",
-        "ppos"
+        "ppos",
+        "pprev"
     ],
 }

2023/20/README.md

@@ -0,0 +1,12 @@
+# Advent of Code - 2023 Day 20
+Here are my solutions to this puzzle.
+
+* Problem instructions: [adventofcode.com/2023/day/20](https://adventofcode.com/2023/day/20)
+* Input: [adventofcode.com/2023/day/20/input](https://adventofcode.com/2023/day/20/input)
+
+Fetch input by exporting `$AOC_SESSION` in your shell and then:
+```bash
+curl -OJLsb session=$AOC_SESSION adventofcode.com/2023/day/20/input
+```
+
+or run `fetch_input.sh` in this directory.

2023/20/fetch_input.sh

@@ -0,0 +1,5 @@
+#!/usr/bin/env sh
+# Make sure $AOC_SESSION is exported before running this script.
+
+curl --remote-name --remote-header-name --silent --fail -A 'https://erikw.me/contact' --cookie "session=$AOC_SESSION" "https://adventofcode.com/2023/day/20/input"
+test "$?" -eq 0 && echo "Fetched input" && exit 0 || echo "Failed to fetch input" && exit 1

2023/20/input1.0

@@ -0,0 +1,5 @@
+broadcaster -> a, b, c
+%a -> b
+%b -> c
+%c -> inv
+&inv -> a

2023/20/input1.1

@@ -0,0 +1,5 @@
+broadcaster -> a
+%a -> inv, con
+&inv -> b
+%b -> con
+&con -> output

2023/20/instructions.url

@@ -0,0 +1,2 @@
+[InternetShortcut]
+URL = https://adventofcode.com/2023/day/20

2023/20/mermaid.py

@@ -0,0 +1,112 @@
+#!/usr/bin/env python3
+import fileinput
+from pprint import pprint
+from python_mermaid.diagram import MermaidDiagram, Node, Link
+
+
+MODULE_BUTTON = "button"
+MODULE_BROADCASTER = "broadcaster"
+MODULE_FINAL = "rx"
+
+STATE_ON = True
+STATE_OFF = False
+
+TYPE_UNTYPED = '-'
+TYPE_FLIPFLOP = '%'
+TYPE_CONJUNCTION = '&'
+
+PULSE_HIGH = True
+PULSE_LOW = False
+
+
+def read_module_configuration():
+    mod_conf = {
+        MODULE_BUTTON: {"type": TYPE_UNTYPED, "dest_names": [MODULE_BROADCASTER]}
+    }
+    for line in fileinput.input():
+        part_name, part_destinations = line.rstrip("\n").split(" -> ")
+
+        if part_name[0] in [TYPE_FLIPFLOP, TYPE_CONJUNCTION]:
+            type = part_name[0]
+            name = part_name[1:]
+        else:
+            type = TYPE_UNTYPED
+            name = part_name
+        destination_names = part_destinations.split(", ")
+
+        if type == TYPE_UNTYPED:
+            mod_conf[name] = {"type": type, "dest_names": destination_names}
+        elif type == TYPE_FLIPFLOP:
+            mod_conf[name] = {"type": type, "dest_names": destination_names, "state": STATE_OFF}
+        elif type == TYPE_CONJUNCTION:
+            mod_conf[name] = {"type": type, "dest_names": destination_names, "input_mem": {}}
+
+    for name in mod_conf:
+        for dest_name in mod_conf[name]["dest_names"]:
+            if dest_name in mod_conf and mod_conf[dest_name]["type"] == TYPE_CONJUNCTION:
+                mod_conf[dest_name]["input_mem"][name] = PULSE_LOW
+
+    return mod_conf
+
+
+def push_button(mod_conf):
+    final_mod_pulses = [0, 0]
+    pulses = deque([(MODULE_BUTTON, PULSE_LOW, MODULE_BROADCASTER)])
+
+    while pulses:
+        name_from, pulse, name_to = pulses.popleft()
+        # print(f"{name_from} -{"high" if pulse else "low"}-> {name_to}")
+
+        if name_to == MODULE_FINAL:
+            final_mod_pulses[bool(pulse)] += 1
+
+        if name_to not in mod_conf:
+            continue
+
+        module = mod_conf[name_to]
+        if module["type"] == TYPE_UNTYPED:
+            for dest_name in module["dest_names"]:
+                pulses.append((name_to, pulse, dest_name))
+        elif module["type"] == TYPE_FLIPFLOP:
+            if pulse == PULSE_LOW:
+                module["state"] = not module["state"]
+                pulse_out = module["state"]
+                for dest_name in module["dest_names"]:
+                    pulses.append((name_to, pulse_out, dest_name))
+        elif module["type"] == TYPE_CONJUNCTION:
+            module["input_mem"][name_from] = pulse
+            pulse_out = PULSE_LOW if all(module["input_mem"].values()) else PULSE_HIGH
+            for dest_name in module["dest_names"]:
+                pulses.append((name_to, pulse_out, dest_name))
+
+
+    return final_mod_pulses
+
+def main():
+    mod_conf = read_module_configuration()
+    pprint(mod_conf)
+
+    nodes = {
+        MODULE_FINAL: Node(MODULE_FINAL, f'{TYPE_UNTYPED}{MODULE_FINAL}')
+    }
+    links = []
+    for name, module in mod_conf.items():
+        nodes[name] = Node(name, f'{module["type"]}{name}')
+
+    for name, module in mod_conf.items():
+        for dest_name in module["dest_names"]:
+            links.append(Link(nodes[name], nodes[dest_name]))
+
+    chart = MermaidDiagram(
+        title="Module Configuration",
+        nodes=nodes.values(),
+        links=links
+    )
+    print(chart) # Paste output at https://mermaid.live/
+    # More specifically accessible here:
+    # https://mermaid.live/edit#pako:eNptVrmS2zoQ_BUVqqxI2lpJK-2agRM7deTM5gtI8RIPkIIgFq2t_ffXMwMQdNlZNwgM5uoB39W5z3IVqe12G2t7sW0erb732b3NV197XVzKu0nspdex5h2lSYZqFWsz_YrV1kyx-i_W6d3aXtOCIF4cUyx8GlMmA5NBSGlB1qVlUtX0paqZPDIij0y-GP5imJiSiCmZ2IKILcT0wKYHuXTiS8Uty8QK0RURXTG5nYnczkzOTM5CrOYzEkLBpgsxXfG2SrYZjse44PjLIF9S0yfZObnZ3HBCApUI2f5D7OsbJULfhLAVLVY6jrCTCKeRyDTKzZwvI_mynBUrWSnZ21K8rR9E6oeQlkkrKSK_1qO4U1-J1FcmDZ1ZN3Km5EtLubRkd0pxJ2OSCWnIwKdGDLQNkbaRe25cCgmutfxFSq5bDlvc6bjKncsOm34ULpNEUld_Nm3E9JW3XWWbYUeNONrypa1cWnRcvk6qTAbWZzFQ8JlCzljOm3UNxG0ySptURNaVkJbz1oo7DW9r5EvKBlIx0HJ92nohjBWU82W17ASIQxbhD7QhGAWGNASjIlCGYORzxvAFIhGMwKCRsG5KwYgECgn2PYYQIBbBKMuM6ew4CUZVIRvBqMmMyY6u3NmJBBTWPYbUoaWw7jF6FbISjOaaMboBCnN7UhJY2GNcTqCNGUMNkJq7q_pDaS7A4h-L6J-_F6G_vxchPcgz-OAx2gRKFYwJNmO0wozTBca8mHG5xAs70CIEH_I_45q0H2L3mOxMY1j3uKG61yHnHmO0YTi49TPNhuB__XD-1wGTzboN_o8m9GF9dTWaaES4BBYBQ8gzzhbrlGSPx8VZzGBMl5CHsgg2Pab8Zz52sul8wJjHlAl58xhPBgaOqwXtcTrCJJgx2dRtiKtzMeJRweARfOUWCvXymPtwce-MDU2jYN9jPCAYTM5-EzD77PzEUzJjOlt0Dl9pWgUte4yRPWM8NmFPGXC32ENy8JhiLMaQf49Zj0OwOVahlzwm-1UV5obH5KfHeMxnTDrymOriMc2rdtFXTRVy6zEeLIzTkCuPMd4xWf1-tVGluWQqsuaeb1SXmy4hqt5jvVrFylZ5l8cqAswSejNi_YEzQ6J_9n3nj5n-XlYqKpL2BnYfssTm3y4J_nDmLcnd9j9-6_N8JNdZbr72d21VtNsd2KaK3tWkou3u7fXp-Hx4Ox1f97vDaaN-q2j__PS2-_z6utudDi-HE7Z8bNSDndg_HY6n0_7t8-748rw_vJyOG5VnF9ub7_JHxj9mH_8DJh0Aag
+
+
+
+if __name__ == '__main__':
+	main()

2023/20/output1.0

@@ -0,0 +1 @@
+32000000

2023/20/output1.1

@@ -0,0 +1 @@
+11687500

2023/20/output2.0

@@ -0,0 +1,97 @@
+#!/usr/bin/env python3
+import fileinput
+from pprint import pprint
+from collections import deque
+from math import prod
+
+PUSHES = 1000
+
+MODULE_BUTTON = "button"
+MODULE_BROADCASTER = "broadcaster"
+
+STATE_ON = True
+STATE_OFF = False
+
+TYPE_UNTYPED = '-'
+TYPE_FLIPFLOP = '%'
+TYPE_CONJUNCTION = '&'
+
+PULSE_HIGH = True
+PULSE_LOW = False
+
+
+def read_module_configuration():
+    mod_conf = {
+        MODULE_BUTTON: {"type": TYPE_UNTYPED, "dest_names": [MODULE_BROADCASTER]}
+    }
+    for line in fileinput.input():
+        part_name, part_destinations = line.rstrip("\n").split(" -> ")
+
+        if part_name[0] in [TYPE_FLIPFLOP, TYPE_CONJUNCTION]:
+            type = part_name[0]
+            name = part_name[1:]
+        else:
+            type = TYPE_UNTYPED
+            name = part_name
+        destination_names = part_destinations.split(", ")
+
+        if type == TYPE_UNTYPED:
+            mod_conf[name] = {"type": type, "dest_names": destination_names}
+        elif type == TYPE_FLIPFLOP:
+            mod_conf[name] = {"type": type, "dest_names": destination_names, "state": STATE_OFF}
+        elif type == TYPE_CONJUNCTION:
+            mod_conf[name] = {"type": type, "dest_names": destination_names, "input_mem": {}}
+
+    for name in mod_conf:
+        for dest_name in mod_conf[name]["dest_names"]:
+            if dest_name in mod_conf and mod_conf[dest_name]["type"] == TYPE_CONJUNCTION:
+                mod_conf[dest_name]["input_mem"][name] = PULSE_LOW
+
+    return mod_conf
+
+
+def push_button(mod_conf):
+    nbr_pulses = [0, 0]
+    pulses = deque([(MODULE_BUTTON, PULSE_LOW, MODULE_BROADCASTER)])
+
+    while pulses:
+        name_from, pulse, name_to = pulses.popleft()
+        # print(f"{name_from} -{"high" if pulse else "low"}-> {name_to}")
+
+        nbr_pulses[bool(pulse)] += 1
+
+        if name_to not in mod_conf:
+            continue
+
+        module = mod_conf[name_to]
+        if module["type"] == TYPE_UNTYPED:
+            for dest_name in module["dest_names"]:
+                pulses.append((name_to, pulse, dest_name))
+        elif module["type"] == TYPE_FLIPFLOP:
+            if pulse == PULSE_LOW:
+                module["state"] = not module["state"]
+                pulse_out = module["state"]
+                for dest_name in module["dest_names"]:
+                    pulses.append((name_to, pulse_out, dest_name))
+        elif module["type"] == TYPE_CONJUNCTION:
+            module["input_mem"][name_from] = pulse
+            pulse_out = PULSE_LOW if all(module["input_mem"].values()) else PULSE_HIGH
+            for dest_name in module["dest_names"]:
+                pulses.append((name_to, pulse_out, dest_name))
+
+
+    return nbr_pulses
+
+def main():
+    mod_conf = read_module_configuration()
+
+    pulses_tot = [0, 0]
+    for _ in range(PUSHES):
+        pulses = push_button(mod_conf)
+        pulses_tot[0] += pulses[0]
+        pulses_tot[1] += pulses[1]
+
+    print(prod(pulses_tot))
+
+if __name__ == '__main__':
+	main()

2023/20/part1.py

@@ -0,0 +1,115 @@
+#!/usr/bin/env python3
+import fileinput
+from collections import deque
+import math
+
+
+MODULE_BUTTON = "button"
+MODULE_BROADCASTER = "broadcaster"
+MODULE_FINAL = "rx"
+
+STATE_ON = True
+STATE_OFF = False
+
+TYPE_UNTYPED = 'u'
+TYPE_FLIPFLOP = '%'
+TYPE_CONJUNCTION = '&'
+
+PULSE_HIGH = True
+PULSE_LOW = False
+
+
+def read_module_configuration():
+    mod_conf = {
+        MODULE_BUTTON: {"type": TYPE_UNTYPED, "dest_names": [MODULE_BROADCASTER], "input_names": []},
+        MODULE_FINAL: {"type": TYPE_UNTYPED, "dest_names": [], "input_names": []},
+    }
+    for line in fileinput.input():
+        part_name, part_destinations = line.rstrip("\n").split(" -> ")
+
+        if part_name[0] in [TYPE_FLIPFLOP, TYPE_CONJUNCTION]:
+            type = part_name[0]
+            name = part_name[1:]
+        else:
+            type = TYPE_UNTYPED
+            name = part_name
+        destination_names = part_destinations.split(", ")
+
+        if type == TYPE_UNTYPED:
+            mod_conf[name] = {"type": type, "dest_names": destination_names, "input_names": []}
+        elif type == TYPE_FLIPFLOP:
+            mod_conf[name] = {"type": type, "dest_names": destination_names, "state": STATE_OFF, "input_names": []}
+        elif type == TYPE_CONJUNCTION:
+            mod_conf[name] = {"type": type, "dest_names": destination_names, "input_mem": {}, "input_names": []}
+
+    for name in mod_conf:
+        for dest_name in mod_conf[name]["dest_names"]:
+            if dest_name in mod_conf and mod_conf[dest_name]["type"] == TYPE_CONJUNCTION:
+                mod_conf[dest_name]["input_mem"][name] = PULSE_LOW
+            if dest_name in mod_conf:
+                mod_conf[dest_name]["input_names"].append(name)
+
+    return mod_conf
+
+
+def find_min_presses(mod_conf):
+    """
+    # h/t https://www.reddit.com/r/adventofcode/comments/18mmfxb/comment/ke5a5fc/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button
+    # With manual analysis of output from mermaid.py, it is concluded that for my input:
+    # * rx is connected as: [&lr, &nl, &vr, &gt] -> &jq -> rx
+    # * further it can be seen that those earlier 4 conjunctions all go to a different sub graph, namely the 4 subgraphs branching from module broadcaster.
+    # * assume those sub-graphs have their own cycles, and that the first time a low input arrives at them, the number of presses up til that point is the cycle (this is universaily not the case, as the presses leading up to the first low signal could be an init sequence before the network has stabilized). Why low signal? Because all last nodes are inverters 4& -> 1& -> rx, meaning low to first level mean low to rx.
+    # * thus period(rx) = lcd(period(&lr), period(&nl), period(&vr), period(&jq))
+    """
+    assert len(mod_conf[MODULE_FINAL]["input_names"]) == 1
+    module_prev = mod_conf[MODULE_FINAL]["input_names"][0]
+
+    assert len(mod_conf[module_prev]["input_names"]) == 4
+    modules_pprev = mod_conf[module_prev]["input_names"]
+
+    presses = 0
+    periods = {}
+    while len(periods) < len(modules_pprev):
+        presses += 1
+
+        final_mod_pulses = [0, 0]
+        pulses = deque([(MODULE_BUTTON, PULSE_LOW, MODULE_BROADCASTER)])
+
+        while pulses:
+            name_from, pulse, name_to = pulses.popleft()
+
+            if name_to in modules_pprev and pulse == PULSE_LOW and name_to not in periods:
+                periods[name_to] = presses
+
+            if name_to == MODULE_FINAL:
+                final_mod_pulses[bool(pulse)] += 1
+
+            if name_to not in mod_conf:
+                continue
+
+            module = mod_conf[name_to]
+            if module["type"] == TYPE_UNTYPED:
+                for dest_name in module["dest_names"]:
+                    pulses.append((name_to, pulse, dest_name))
+            elif module["type"] == TYPE_FLIPFLOP:
+                if pulse == PULSE_LOW:
+                    module["state"] = not module["state"]
+                    pulse_out = module["state"]
+                    for dest_name in module["dest_names"]:
+                        pulses.append((name_to, pulse_out, dest_name))
+            elif module["type"] == TYPE_CONJUNCTION:
+                module["input_mem"][name_from] = pulse
+                pulse_out = PULSE_LOW if all(module["input_mem"].values()) else PULSE_HIGH
+                for dest_name in module["dest_names"]:
+                    pulses.append((name_to, pulse_out, dest_name))
+
+
+    return math.lcm(*periods.values())
+
+def main():
+    mod_conf = read_module_configuration()
+    presses = find_min_presses(mod_conf)
+    print(presses)
+
+if __name__ == '__main__':
+	main()