#!/usr/bin/env luajit
require("utils")

function parse(line)
	local number = {}
	local depth = 0
	for char in chars(line) do
		if char == "[" then
			depth = depth + 1
		elseif char == "]" then
			depth = depth - 1
		elseif char ~= "," then
			table.insert(number, { d=depth, n=tonumber(char) })
		end
	end
	return number
end

function add(a, b)
	local sum = {}
	for i, digit in ipairs(a) do
		table.insert(sum, { d = digit.d + 1, n = digit.n })
	end
	for i, digit in ipairs(b) do
		table.insert(sum, { d = digit.d + 1, n = digit.n })
	end
	return sum
end

function explode(a)
	local new = {}
	local exploded = false
	local i = 1
	while i <= #a do
		if exploded or a[i].d <= 4 then
			table.insert(new, a[i])
			i = i + 1
		else
			exploded = true
			if #new > 0 then
				new[#new].n = new[#new].n + a[i].n
			end
			table.insert(new, { d = a[i].d - 1, n = 0 })
			if #a >= i + 2 then
				table.insert(new, { d = a[i + 2].d, n = a[i + 1].n + a[i + 2].n })
			end
			i = i + 3
		end
	end
	return exploded, new
end

-- printtable({ explode(parse("[[[[[9,8],1],2],3],4]")) })
-- printtable({ explode(parse("[7,[6,[5,[4,[3,2]]]]]")) })
-- printtable({ explode(parse("[[6,[5,[4,[3,2]]]],1]")) })
-- printtable({ explode(parse("[[3,[2,[1,[7,3]]]],[6,[5,[4,[3,2]]]]]")) })
-- printtable({ explode(parse("[[3,[2,[8,0]]],[9,[5,[4,[3,2]]]]]")) })

function split(a)
	local new = {}
	local split = false
	for i, digit in ipairs(a) do
		if split or digit.n < 10 then
			table.insert(new, digit)
		else
			split = true
			table.insert(new, { d = digit.d + 1, n = math.floor(digit.n / 2) })
			table.insert(new, { d = digit.d + 1, n = math.ceil(digit.n / 2) })
		end
	end
	return split, new
end

function reduce(a)
	local changed = true
	repeat
		changed, a = explode(a)
		if not changed then
			changed, a = split(a)
		end
	until not changed
	return a
end

function reconstruct(number)
	local function go(d, c)
		local left, right
		if number[c].d > d then
			left, c = go(d + 1, c)
			right, c = go(d + 1, c)
			return { left, right }, c
		else
			return number[c].n, c + 1
		end
	end
	return go(0, 1)
end

function printnumber(a)
	local function go(a)
		if type(a) == "number" then
			io.write(tostring(a))
		else
			io.write("[")
			go(a[1])
			io.write(",")
			go(a[2])
			io.write("]")
		end
	end
	go(reconstruct(a))
	io.write("\n")
end

-- printnumber(reduce(parse("[[[[[4,3],4],4],[7,[[8,4],9]]],[1,1]]")))
-- printnumber(reduce(add(parse("[[[[4,3],4],4],[7,[[8,4],9]]]"),parse("[1,1]"))))
-- printnumber(parse("[[[0,[4,5]],[0,0]],[[[4,5],[2,6]],[9,5]]]"))
-- printtable(parse("[[[0,[4,5]],[0,0]],[[[4,5],[2,6]],[9,5]]]"))
-- printnumber(add(parse("[[[0,[4,5]],[0,0]],[[[4,5],[2,6]],[9,5]]]"),parse("[7,[[[3,7],[4,3]],[[6,3],[8,8]]]]")))
-- printnumber(reduce(add(parse("[[[0,[4,5]],[0,0]],[[[4,5],[2,6]],[9,5]]]"),parse("[7,[[[3,7],[4,3]],[[6,3],[8,8]]]]"))))

function magnitude(a)
	local function go(a)
		if type(a) == "number" then
			return a
		else
			return 3 * go(a[1]) + 2 * go(a[2])
		end
	end
	return go(reconstruct(a))
end

local f = io.open(arg[3])
local number = parse(f:read("*l"))
local line = f:read("*l")
while line do
	number = reduce(add(number, parse(line)))
	line = f:read("*l")
end

print(magnitude(number))