diff --git a/day3/day3ai.lua b/day3/day3ai.lua
new file mode 100644
index 0000000..d0eb7a5
--- /dev/null
+++ b/day3/day3ai.lua
@@ -0,0 +1,54 @@
+for i = 1, 1000 do
+-- Open the file for reading
+local file = assert(io.open("strings.txt", "r"))
+
+-- Initialize a variable to store the sum of scores
+local score = 0
+
+-- Read each line from the file
+for line in file:lines() do
+  -- Split the line in half
+  local first_half = line:sub(1, #line / 2)
+  local second_half = line:sub(#line / 2 + 1)
+
+  -- Create a table to store the characters in each half
+  local first_half_chars = {}
+  local second_half_chars = {}
+
+  -- Iterate over each character in each half and store it in the table
+  for i = 1, #first_half do
+    first_half_chars[first_half:sub(i, i)] = true
+  end
+  for i = 1, #second_half do
+    second_half_chars[second_half:sub(i, i)] = true
+  end
+
+  -- Create a table to store the characters that have already been counted
+  local counted_chars = {}
+
+  -- Iterate over each character in the first half again
+  -- and check if it exists in the second half
+  for i = 1, #first_half do
+    local char = first_half:sub(i, i)
+    if second_half_chars[char] and not counted_chars[char] then
+      -- If it does and it hasn't been counted yet,
+      -- assign it a score and add it to the sum of scores
+      local score_value = 0
+      if char:lower() == char then
+        -- If the character is lowercase, its score is its ASCII value - 96
+        score_value = string.byte(char) - 96
+      else
+        -- If the character is uppercase, its score is its ASCII value - 64 + 26
+        score_value = string.byte(char) - 64 + 26
+      end
+      score = score + score_value
+
+      -- Add the character to the counted_chars table so it won't be counted again
+      counted_chars[char] = true
+    end
+  end
+end
+
+-- Print the final sum of scores
+print(score)
+end