feat: add twosum solution in lua

Author: João Pedro

leetcode/1 - twosum/two-sum.lua

@@ -0,0 +1,30 @@
+function TwoSumQuadradic(nums, target)
+    for i = 1, #nums do
+        for j = i + 1, #nums do
+            if nums[i] + nums[j] == target then 
+                return i, j 
+            end
+        end
+    end
+
+    return nil
+end
+
+function TwoSum(nums, target)
+    local seen = {}
+
+    for i, num in ipairs(nums) do
+        if seen[num] then 
+            return seen[num], i 
+        end
+        seen[target - num] = i
+    end
+
+    return nil
+end
+
+local nums = {2, 15, 11, 7}
+local target = 9
+
+print(TwoSumQuadratic(nums, target))
+print(TwoSum(nums, target))