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 # [Advent of Code 2015](https://adventofcode.com/2015)
 
-| Solved | Day | Language
-|:------:|:---:|:---------
-| ✓      | 01  | Ruby
-| ✓      | 02  | Ruby
-| ✓      | 03  | Ruby
-| ✓      | 04  | Rust
-| ✓      | 05  | Ruby
-| ✓      | 06  | Ruby
-| ✓      | 07  | Rust
-| ✓      | 08  | Ruby
-| ✓      | 09  | Rust
-| ✓      | 10  | Ruby
-| ✓      | 11  | Ruby
-| ✓      | 12  | Ruby
-| ✓      | 13  | Ruby
-| ✓      | 14  | Ruby
-| ✓      | 15  | Ruby
-| ✓      | 16  | Ruby
-|        | 17  |
-|        | 18  |
-|        | 19  |
-|        | 20  |
-|        | 21  |
-|        | 22  |
-|        | 23  |
-|        | 24  |
-|        | 25  |
+| Solved   | Day    | Topics                | Language   |
+| :------: | :----: | :-------------------- | :--------- |
+| ✓        | 01     | Arithmetic            | Ruby       |
+| ✓        | 02     | Geometry              | Ruby       |
+| ✓        | 03     | Navigation            | Ruby       |
+| ✓        | 04     | Hashing               | Rust       |
+| ✓        | 05     | String validation     | Ruby       |
+| ✓        | 06     | Arithmetic            | Ruby       |
+| ✓        | 07     | Interpreting          | Rust       |
+| ✓        | 08     | String escaping       | Ruby       |
+| ✓        | 09     | Graph search          | Rust       |
+| ✓        | 10     | Parsing               | Ruby       |
+| ✓        | 11     | Password validation   | Ruby       |
+| ✓        | 12     | Recursion             | Ruby       |
+| ✓        | 13     | Optimization          | Ruby       |
+| ✓        | 14     | Score calculation     | Ruby       |
+| ✓        | 15     | Permutations          | Ruby       |
+| ✓        | 16     | Searching             | Ruby       |
+|          | 17     | Combinations          |            |
+|          | 18     |                       |            |
+|          | 19     |                       |            |
+|          | 20     |                       |            |
+|          | 21     |                       |            |
+|          | 22     |                       |            |
+|          | 23     |                       |            |
+|          | 24     |                       |            |
+|          | 25     |                       |            |