feat(day-12): completed day 12 with lua

Author: NishantJoshi00

README.md

@@ -17,7 +17,7 @@ Here is the list of the problems solved and language used to solve them
 - [x] Day 9 - OCaml
 - [x] Day 10 - Zig
 - [x] Day 11 - Octave/Matlab
-- [ ] Day 12
+- [x] Day 12 - Lua
 - [ ] Day 13
 - [ ] Day 14
 - [ ] Day 15

day-12/.gitignore

@@ -0,0 +1 @@
+*.in

day-12/Makefile

@@ -0,0 +1,5 @@
+run: solution.lua
+	luajit solution.lua
+
+run2: solution2.lua
+	luajit solution2.lua

day-12/solution.lua

@@ -0,0 +1,105 @@
+-- @param line string
+-- @return string
+-- @return integer[]
+function parse_input(line)
+  local _, _, data, parity = string.find(line, "(.*) (.*)")
+  local parity_list = {}
+  for i in string.gmatch(parity, '([^,]+)') do
+    table.insert(parity_list, tonumber(i))
+  end
+
+  return data, parity_list
+end
+
+function inspect(data, indent)
+  indent = indent or 0
+  local indentStr = string.rep("  ", indent)
+
+  if type(data) == "table" then
+    local output = "{\n"
+    for key, value in pairs(data) do
+      local keyStr = type(key) == "string" and '["' .. key .. '"]' or "[" .. tostring(key) .. "]"
+      output = output .. indentStr .. "  " .. keyStr .. " = " .. inspect(value, indent + 1) .. ",\n"
+    end
+    return output .. indentStr .. "}"
+  else
+    return tostring(data)
+  end
+end
+
+function solve(data, nums, cache)
+  if cache == nil then
+    cache = {}
+  end
+  local cache_key = data .. table.concat(nums, "")
+  local cache_output = cache[cache_key]
+  if cache_output ~= nil then
+    return cache_output
+  end
+  if data == "" then
+    if #nums == 0 then
+      return 1
+    else
+      return 0
+    end
+  end
+
+  if #nums == 0 then
+    if string.find(data, "#") ~= nil then
+      cache[cache_key] = 0
+      return 0
+    else
+      cache[cache_key] = 1
+      return 1
+    end
+  end
+
+  local output = 0
+
+  if string.find(string.sub(data, 1, 1), "[.?]") ~= nil then
+    output = output + solve(string.sub(data, 2), nums, cache)
+  end
+
+  if string.find(string.sub(data, 1, 1), "[#?]") ~= nil then
+    if ((nums[1] <= #data)
+          and (string.find(string.sub(data, 1, nums[1]), "[.]") == nil)
+          and (nums[1] == #data or string.sub(data, nums[1] + 1, nums[1] + 1) ~= "#")) then
+      local new_table = table.list_copy(nums);
+      table.remove(new_table, 1)
+      output = output + solve(string.sub(data, nums[1] + 2), new_table, cache)
+    end
+  end
+  cache[cache_key] = output
+  return output
+end
+
+function merge(t1, t2)
+  local output = {}
+  for _, v in ipairs(t1) do
+    table.insert(output, v)
+  end
+
+  for _, v in ipairs(t2) do
+    table.insert(output, v)
+  end
+  return output
+end
+
+function table.list_copy(t)
+  local output = {}
+  for _, v in ipairs(t) do
+    table.insert(output, v)
+  end
+  return output
+end
+
+local total = 0
+
+while true do
+  local line = io.read("l")
+  if line == nil then break; end
+  local data, parity_list = parse_input(line)
+  total = total + solve(data, parity_list)
+end
+
+print(total)

day-12/solution2.lua

@@ -0,0 +1,130 @@
+-- @param line string
+-- @return string
+-- @return integer[]
+function parse_input(line)
+  local _, _, data, parity = string.find(line, "(.*) (.*)")
+  local parity_list = {}
+  for i in string.gmatch(parity, '([^,]+)') do
+    table.insert(parity_list, tonumber(i))
+  end
+
+  return data, parity_list
+end
+
+function inspect(data, indent)
+  indent = indent or 0
+  local indentStr = string.rep("  ", indent)
+
+  if type(data) == "table" then
+    local output = "{\n"
+    for key, value in pairs(data) do
+      local keyStr = type(key) == "string" and '["' .. key .. '"]' or "[" .. tostring(key) .. "]"
+      output = output .. indentStr .. "  " .. keyStr .. " = " .. inspect(value, indent + 1) .. ",\n"
+    end
+    return output .. indentStr .. "}"
+  else
+    return tostring(data)
+  end
+end
+
+function solve(data, nums, cache)
+  if cache == nil then
+    cache = {}
+  end
+  local cache_key = data .. table.concat(nums, "")
+  local cache_output = cache[cache_key]
+  if cache_output ~= nil then
+    return cache_output
+  end
+  if data == "" then
+    if #nums == 0 then
+      return 1
+    else
+      return 0
+    end
+  end
+
+  if #nums == 0 then
+    if string.find(data, "#") ~= nil then
+      cache[cache_key] = 0
+      return 0
+    else
+      cache[cache_key] = 1
+      return 1
+    end
+  end
+
+  local output = 0
+
+  if string.find(string.sub(data, 1, 1), "[.?]") ~= nil then
+    output = output + solve(string.sub(data, 2), nums, cache)
+  end
+
+  if string.find(string.sub(data, 1, 1), "[#?]") ~= nil then
+    if ((nums[1] <= #data)
+          and (string.find(string.sub(data, 1, nums[1]), "[.]") == nil)
+          and (nums[1] == #data or string.sub(data, nums[1] + 1, nums[1] + 1) ~= "#")) then
+      local new_table = table.list_copy(nums);
+      table.remove(new_table, 1)
+      output = output + solve(string.sub(data, nums[1] + 2), new_table, cache)
+    end
+  end
+  cache[cache_key] = output
+  return output
+end
+
+function merge(t1, t2)
+  local output = {}
+  for _, v in ipairs(t1) do
+    table.insert(output, v)
+  end
+
+  for _, v in ipairs(t2) do
+    table.insert(output, v)
+  end
+  return output
+end
+
+function repeat_data(t, count, sep)
+  if type(t) == "table" then
+    local output = {}
+    local del = {}
+    if sep ~= nil then
+      del = sep
+    end
+    for i = 1, count do
+      output = merge(merge(output, t), del)
+    end
+    return output
+  else
+    local output = t
+    for i = 1, count - 1 do
+      if sep ~= nil then
+        output = output .. sep
+      end
+      output = output .. t
+    end
+    return output
+  end
+end
+
+function table.list_copy(t)
+  local output = {}
+  for _, v in ipairs(t) do
+    table.insert(output, v)
+  end
+  return output
+end
+
+local total = 0
+
+while true do
+  local line = io.read("l")
+  if line == nil then break; end
+  local data, parity_list = parse_input(line)
+  data = repeat_data(data, 5, "?")
+  parity_list = repeat_data(parity_list, 5)
+  total = total + solve(data, parity_list)
+end
+
+print(total)