return (function()
local builders = {}
local function register(name, f)
builders[name] = f
end
register('llpeg', function() return require [[Module:User:Cscott/llpeg]] end)
register('util', function(myrequire)
local function read_wiki_input(func)
return function (frame, ...)
if type(frame)=='string' then
frame = { args = { frame, ... } }
end
local title = mw.title.new(frame.args[1])
local source = title:getContent()
if source == nil then
error("Can't find title " .. tostring(title))
end
source = source:gsub("^%s*<syntaxhighlight[^>]*>\n?", "", 1)
source = source:gsub("</syntaxhighlight[^>]*>%s*$", "", 1)
return func(source, frame.args[2], frame.args[3])
end
end
return {
read_wiki_input = read_wiki_input,
}
end)
register('pqueue', function(myrequire)
--[[ Priority Queue implemented in lua, based on a binary heap.
Copyright (C) 2017 Lucas de Morais Siqueira <lucas.morais.siqueira@gmail.com>
License: zlib
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgement in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
]]--
-- modified by xxopxe@gmail.com
local floor = math.floor
local PriorityQueue = {}
PriorityQueue.__index = PriorityQueue
setmetatable(
PriorityQueue,
{
__call = function ()
local new = {}
setmetatable(new, PriorityQueue)
new:initialize()
return new
end
}
)
function PriorityQueue:initialize()
--[[ Initialization.
Example:
PriorityQueue = require "priority_queue"
pq = PriorityQueue()
]]--
self.heap_val = {}
self.heap_pri = {}
self.current_size = 0
end
function PriorityQueue:empty()
return self.current_size == 0
end
function PriorityQueue:size()
return self.current_size
end
function PriorityQueue:swim()
-- Swim up on the tree and fix the order heap property.
local heap_val = self.heap_val
local heap_pri = self.heap_pri
local floor = floor
local i = self.current_size
while floor(i / 2) > 0 do
local half = floor(i / 2)
if heap_pri[i] < heap_pri[half] then
heap_val[i], heap_val[half] = heap_val[half], heap_val[i]
heap_pri[i], heap_pri[half] = heap_pri[half], heap_pri[i]
end
i = half
end
end
function PriorityQueue:put(v, p)
--[[ Put an item on the queue.
Args:
v: the item to be stored
p(number): the priority of the item
]]--
--
self.current_size = self.current_size + 1
self.heap_val[self.current_size] = v
self.heap_pri[self.current_size] = p
self:swim()
end
function PriorityQueue:sink()
-- Sink down on the tree and fix the order heap property.
local size = self.current_size
local heap_val = self.heap_val
local heap_pri = self.heap_pri
local i = 1
while (i * 2) <= size do
local mc = self:min_child(i)
if heap_pri[i] > heap_pri[mc] then
heap_val[i], heap_val[mc] = heap_val[mc], heap_val[i]
heap_pri[i], heap_pri[mc] = heap_pri[mc], heap_pri[i]
end
i = mc
end
end
function PriorityQueue:min_child(i)
if (i * 2) + 1 > self.current_size then
return i * 2
else
if self.heap_pri[i * 2] < self.heap_pri[i * 2 + 1] then
return i * 2
else
return i * 2 + 1
end
end
end
function PriorityQueue:pop()
-- Remove and return the top priority item
local heap_val = self.heap_val
local heap_pri = self.heap_pri
local retval, retprio = heap_val[1], heap_pri[1]
heap_val[1], heap_pri[1] = heap_val[self.current_size], heap_pri[self.current_size]
heap_val[self.current_size], heap_pri[self.current_size] = nil, nil
self.current_size = self.current_size - 1
self:sink()
return retval, retprio
end
function PriorityQueue:peek()
-- return the top priority item
return self.heap_val[1], self.heap_pri[1]
end
return PriorityQueue
end)
register('day25', function(myrequire)
--[[ DAY 25 ]]--
local l = myrequire('llpeg')
local read_wiki_input = myrequire('util').read_wiki_input
local PriorityQueue = myrequire('pqueue')
--[[ PARSING ]]--
local nl = l.P"\n"
local SKIP = l.S" \t"^0
local patt = l.P{
"Wiring",
Wiring = l.Ct( l.V"Component" * (nl * l.V"Component")^0 * nl^0) * -1,
Component = l.Ct( l.Cg(l.V"Name", "name") * SKIP * l.P":" * SKIP * l.Cg(l.V"ConnectionList", "connections")),
ConnectionList = l.Ct( l.V"Name" * (l.P" " * SKIP * l.V"Name")^0 ),
Name = l.C( l.R"az"^1 ),
}
local Node = {}
Node.__index = Node
function Node:new(p)
return setmetatable(p or {}, self)
end
function Node:addEdge(n)
for _,e in ipairs(self.edges) do
if e == n then return end
end
table.insert(self.edges, n)
end
local function parse(source)
local ast, errlabel, pos = patt:match(source)
if not ast then
error(string.format("Error at pos %s label '%s'", pos, errlabel))
end
-- postprocess
local graph = {}
-- first create all nodes
for _,n in ipairs(ast) do
graph[n.name] = Node:new{ name=n.name, edges={} }
for _,n2 in ipairs(n.connections) do
graph[n2] = Node:new{ name=n2, edges={} }
end
end
-- now create all edges
for _,n in ipairs(ast) do
for _,n2 in ipairs(n.connections) do
graph[n.name]:addEdge(graph[n2])
graph[n2]:addEdge(graph[n.name])
end
end
return graph
end
local function sortedKeys(tbl)
local sorted = {}
for k,_ in pairs(tbl) do
table.insert(sorted, k)
end
table.sort(sorted)
return sorted
end
local function shortestPath(from, to, checkEdge)
local seen = {}
local Q = PriorityQueue()
Q:put({node=from,prev=nil,len=0}, 0)
while not Q:empty() do
local item = Q:pop()
if item.node == to then return item end
if seen[item.node] == nil then
seen[item.node] = true
for _,next in ipairs(item.node.edges) do
if seen[next] == nil then
if checkEdge == nil or checkEdge(item.node, next) then
Q:put({node=next,prev=item,len=item.len+1},item.len+1)
end
end
end
end
end
return nil -- no path found
end
local function part1(source)
--mw.log(source)
local graph = parse(source)
local nodes = sortedKeys(graph)
-- pick a node arbitrarily
local n = graph[nodes[1]]
local clique1, clique2 = { n }, {}
-- try to make paths to every other node in the graph. either:
-- 1) there are more than 3 possible paths => this node is in the same
-- component as n
-- 2) there are only 3 possible paths => this node is in the "other"
-- component
for i=2,#nodes do
local n2 = graph[nodes[i]]
local removedEdges = {}
local function makeKey(a, b) return a.name .. '-' .. b.name end
local noPathFound = false
for i=1,4 do
local path = shortestPath(n, n2, function(a, b)
return removedEdges[makeKey(a,b)] == nil
end)
if path == nil then
noPathFound = true
break
end
-- add this path to the list of removed edges
while path.prev ~= nil do
removedEdges[makeKey(path.node, path.prev.node)] = true
removedEdges[makeKey(path.prev.node, path.node)] = true
path = path.prev
end
end
if noPathFound then
table.insert(clique2, n2)
else
table.insert(clique1, n2)
end
end
--print(#clique1, #clique2)
return #clique1 * #clique2
end
--[[ CLI ] ]--
local do_part1 = false
local use_example = false
local filename
if use_example then
filename = "day25.example"
else
filename = "day25.input"
end
local source = io.input(filename):read("*a")
print(part1(source))
--[ [ END CLI ]]--
return {
part1 = read_wiki_input(part1),
}
end)
local modules = {}
modules['bit32'] = require('bit32')
modules['string'] = require('string')
modules['strict'] = {}
modules['table'] = require('table')
local function myrequire(name)
if modules[name] == nil then
modules[name] = true
modules[name] = (builders[name])(myrequire)
end
return modules[name]
end
return myrequire('day25')
end)()
