{
  "active": true,
  "blurb": "Java is a very widely used Object Oriented programming language. It's safe, simple to use and portable so that you can \"write once, run anywhere\".",
  "exercises": [
    {
      "core": true,
      "difficulty": 1,
      "slug": "hello-world",
      "topics": [
        "strings"
      ],
      "unlocked_by": null,
      "uuid": "f77dc7e3-35a8-4300-a7c8-2c1765e9644d"
    },
    {
      "core": true,
      "difficulty": 1,
      "slug": "two-fer",
      "topics": [
        "conditionals",
        "strings"
      ],
      "unlocked_by": null,
      "uuid": "74515d45-565b-4be2-96c4-77e58efa9257"
    },
    {
      "core": false,
      "difficulty": 1,
      "slug": "reverse-string",
      "topics": [
        "strings"
      ],
      "unlocked_by": "two-fer",
      "uuid": "2c8afeed-480e-41f3-ad58-590fa8f88029"
    },
    {
      "core": false,
      "difficulty": 2,
      "slug": "armstrong-numbers",
      "topics": [
        "integers",
        "mathematics"
      ],
      "unlocked_by": null,
      "uuid": "8e1dd48c-e05e-4a72-bf0f-5aed8dd123f5"
    },
    {
      "core": false,
      "difficulty": 2,
      "slug": "rna-transcription",
      "topics": [
        "loops",
        "maps",
        "strings"
      ],
      "unlocked_by": null,
      "uuid": "8e983ed2-62f7-439a-a144-fb8fdbdf4d30"
    },
    {
      "core": false,
      "difficulty": 3,
      "slug": "pangram",
      "topics": [
        "pattern_matching",
        "regular_expressions",
        "strings"
      ],
      "unlocked_by": null,
      "uuid": "133b0f84-bdc7-4508-a0a1-5732a7db81ef"
    },
    {
      "core": true,
      "difficulty": 3,
      "slug": "hamming",
      "topics": [
        "integers",
        "loops",
        "strings"
      ],
      "unlocked_by": null,
      "uuid": "ce899ca6-9cc7-47ba-b76f-1bbcf2630b76"
    },
    {
      "core": true,
      "difficulty": 3,
      "slug": "gigasecond",
      "topics": [
        "dates",
        "integers",
        "time"
      ],
      "unlocked_by": null,
      "uuid": "bf1641c8-dc0d-4d38-9cfe-b4c132ea3553"
    },
    {
      "core": false,
      "difficulty": 3,
      "slug": "space-age",
      "topics": [
        "conditionals",
        "floating_point_numbers",
        "mathematics"
      ],
      "unlocked_by": null,
      "uuid": "e5b524cd-3a1c-468a-8981-13e8eeccb29d"
    },
    {
      "core": false,
      "difficulty": 3,
      "slug": "acronym",
      "topics": [
        "loops",
        "parsing",
        "searching",
        "strings"
      ],
      "unlocked_by": null,
      "uuid": "c31bbc6d-bdcf-44f7-bf35-5f98752e38d0"
    },
    {
      "core": true,
      "difficulty": 3,
      "slug": "scrabble-score",
      "topics": [
        "games",
        "loops",
        "pattern_matching",
        "strings",
        "transforming"
      ],
      "unlocked_by": null,
      "uuid": "afae9f2d-8baf-4bd7-8d7c-d486337f7c97"
    },
    {
      "core": false,
      "difficulty": 3,
      "slug": "raindrops",
      "topics": [
        "conditionals",
        "integers",
        "mathematics",
        "strings"
      ],
      "unlocked_by": "hello-world",
      "uuid": "d916e4f8-fda1-41c0-ab24-79e8fc3f1272"
    },
    {
      "core": true,
      "difficulty": 3,
      "slug": "difference-of-squares",
      "topics": [
        "integers",
        "loops",
        "mathematics"
      ],
      "unlocked_by": null,
      "uuid": "b0da59c6-1b55-405c-b163-007ebf09f5e8"
    },
    {
      "core": true,
      "difficulty": 3,
      "slug": "secret-handshake",
      "topics": [
        "bitwise_operations",
        "conditionals",
        "cryptography",
        "enumerations",
        "integers",
        "loops",
        "mathematics",
        "transforming"
      ],
      "unlocked_by": null,
      "uuid": "71c7c174-7e2c-43c2-bdd6-7515fcb12a91"
    },
    {
      "core": false,
      "difficulty": 3,
      "slug": "perfect-numbers",
      "topics": [
        "enumerations",
        "exception_handling",
        "filtering",
        "integers",
        "mathematics"
      ],
      "unlocked_by": "difference-of-squares",
      "uuid": "d0dcc898-ec38-4822-9e3c-1a1829c9b2d9"
    },
    {
      "core": false,
      "difficulty": 3,
      "slug": "protein-translation",
      "topics": [
        "arrays",
        "conditionals",
        "loops",
        "strings"
      ],
      "unlocked_by": "two-fer",
      "uuid": "331073b3-bd1a-4868-b767-a64ce9fd9d97"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "proverb",
      "topics": [
        "arrays",
        "loops",
        "strings"
      ],
      "unlocked_by": "two-fer",
      "uuid": "9906491b-a638-408d-86a4-4ad320a92658"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "isbn-verifier",
      "topics": [
        "integers",
        "loops",
        "strings"
      ],
      "unlocked_by": "hamming",
      "uuid": "838bc1d7-b2de-482a-9bfc-c881b4ccb04c"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "sum-of-multiples",
      "topics": [
        "arrays",
        "conditionals",
        "integers",
        "loops",
        "mathematics"
      ],
      "unlocked_by": "difference-of-squares",
      "uuid": "2f244afc-3e7b-4f89-92af-e2b427f4ef35"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "luhn",
      "topics": [
        "algorithms",
        "booleans",
        "loops",
        "mathematics",
        "strings",
        "type_conversion"
      ],
      "unlocked_by": "hamming",
      "uuid": "5227a76c-8ecb-4e5f-b023-6af65a057c41"
    },
    {
      "core": true,
      "difficulty": 4,
      "slug": "matrix",
      "topics": [
        "arrays",
        "integers",
        "loops",
        "pattern_matching",
        "strings",
        "type_conversion"
      ],
      "unlocked_by": null,
      "uuid": "c1d4e0b4-6a0f-4be9-8222-345966621f53"
    },
    {
      "core": true,
      "difficulty": 4,
      "slug": "triangle",
      "topics": [
        "booleans",
        "classes",
        "exception_handling",
        "mathematics"
      ],
      "unlocked_by": null,
      "uuid": "ec268d8e-997b-4553-8c67-8bdfa1ecb888"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "largest-series-product",
      "topics": [
        "integers",
        "loops",
        "mathematics",
        "strings",
        "type_conversion"
      ],
      "unlocked_by": "hamming",
      "uuid": "b7310b6e-435c-4d5f-b2bd-31e586d0f238"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "sieve",
      "topics": [
        "algorithms",
        "integers",
        "lists",
        "loops",
        "mathematics"
      ],
      "unlocked_by": "difference-of-squares",
      "uuid": "6791d01f-bae4-4b63-ae76-86529ac49e36"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "twelve-days",
      "topics": [
        "arrays",
        "conditionals",
        "loops",
        "strings"
      ],
      "unlocked_by": "two-fer",
      "uuid": "581afdbb-dfb6-4dc5-9554-a025b5469a3c"
    },
    {
      "core": true,
      "difficulty": 4,
      "slug": "rotational-cipher",
      "topics": [
        "cryptography",
        "integers",
        "strings"
      ],
      "unlocked_by": null,
      "uuid": "9eb41883-55ef-4681-b5ac-5c2259302772"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "kindergarten-garden",
      "topics": [
        "arrays",
        "enumerations",
        "lists",
        "logic",
        "loops",
        "pattern_recognition",
        "strings"
      ],
      "unlocked_by": "matrix",
      "uuid": "0b92ffee-c092-4ab1-ad78-76c8cf80e1b5"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "collatz-conjecture",
      "topics": [
        "conditionals",
        "exception_handling",
        "integers",
        "mathematics",
        "recursion"
      ],
      "unlocked_by": "triangle",
      "uuid": "1500d39a-c9d9-4d3a-9e77-fdc1837fc6ad"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "nth-prime",
      "topics": [
        "arrays",
        "exception_handling",
        "integers",
        "lists",
        "loops"
      ],
      "unlocked_by": "triangle",
      "uuid": "2c69db99-648d-4bd7-8012-1fbdeff6ca0a"
    },
    {
      "core": true,
      "difficulty": 4,
      "slug": "saddle-points",
      "topics": [
        "arrays",
        "conditionals",
        "integers",
        "lists",
        "loops",
        "mathematics",
        "matrices",
        "sets"
      ],
      "unlocked_by": null,
      "uuid": "8dfc2f0d-1141-46e9-95e2-6f35ccf6f160"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "error-handling",
      "topics": [
        "exception_handling",
        "optional_values"
      ],
      "unlocked_by": "triangle",
      "uuid": "846ae792-7ca7-43e1-b523-bb1ec9fa08eb"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "diamond",
      "topics": [
        "arrays",
        "lists",
        "loops",
        "strings",
        "text_formatting"
      ],
      "unlocked_by": "two-fer",
      "uuid": "ecbd997b-86f4-4e11-9ff0-706ac2899415"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "isogram",
      "topics": [
        "conditionals",
        "loops",
        "parsing",
        "strings"
      ],
      "unlocked_by": "hello-world",
      "uuid": "c3e89c7c-3a8a-4ddc-b653-9b0ff9e1d7d8"
    },
    {
      "core": false,
      "difficulty": 4,
      "slug": "variable-length-quantity",
      "topics": [
        "bitwise_operations",
        "conditionals",
        "exception_handling",
        "lists",
        "loops",
        "transforming"
      ],
      "unlocked_by": "secret-handshake",
      "uuid": "d8a2c7ba-2040-4cfe-ab15-f90b3b61dd89"
    },
    {
      "core": true,
      "difficulty": 5,
      "slug": "flatten-array",
      "topics": [
        "arrays",
        "lists",
        "loops",
        "recursion"
      ],
      "unlocked_by": null,
      "uuid": "a732a838-8170-458a-a85e-d6b4c46f97a1"
    },
    {
      "core": false,
      "difficulty": 5,
      "slug": "pig-latin",
      "topics": [
        "arrays",
        "lists",
        "strings",
        "transforming"
      ],
      "unlocked_by": "hello-world",
      "uuid": "38bc80ae-d842-4c04-a797-48edf322504d"
    },
    {
      "core": false,
      "difficulty": 5,
      "slug": "phone-number",
      "topics": [
        "conditionals",
        "pattern_matching",
        "regular_expressions",
        "strings"
      ],
      "unlocked_by": "hamming",
      "uuid": "5f9139e7-9fbb-496a-a0d7-a946283033de"
    },
    {
      "core": false,
      "difficulty": 5,
      "slug": "nucleotide-count",
      "topics": [
        "conditionals",
        "exception_handling",
        "integers",
        "maps",
        "parsing",
        "searching",
        "strings"
      ],
      "unlocked_by": "hamming",
      "uuid": "2d80fdfc-5bd7-4b67-9fbe-8ab820d89051"
    },
    {
      "core": true,
      "difficulty": 5,
      "slug": "word-count",
      "topics": [
        "conditionals",
        "integers",
        "loops",
        "maps",
        "strings"
      ],
      "unlocked_by": null,
      "uuid": "3603b770-87a5-4758-91f3-b4d1f9075bc1"
    },
    {
      "core": false,
      "difficulty": 5,
      "slug": "run-length-encoding",
      "topics": [
        "integers",
        "pattern_matching",
        "strings",
        "transforming"
      ],
      "unlocked_by": "rotational-cipher",
      "uuid": "4499a3f9-73a7-48bf-8753-d5b6abf588c9"
    },
    {
      "core": true,
      "difficulty": 5,
      "slug": "robot-name",
      "topics": [
        "pattern_matching",
        "randomness",
        "regular_expressions",
        "strings",
        "text_formatting"
      ],
      "unlocked_by": null,
      "uuid": "d7c2eed9-64c7-4c4a-b45d-c787d460337f"
    },
    {
      "core": false,
      "difficulty": 5,
      "slug": "prime-factors",
      "topics": [
        "arrays",
        "conditionals",
        "integers",
        "lists",
        "loops",
        "mathematics"
      ],
      "unlocked_by": "triangle",
      "uuid": "599c08ec-7338-46ed-99f8-a76f78f724e6"
    },
    {
      "core": false,
      "difficulty": 5,
      "slug": "allergies",
      "topics": [
        "booleans",
        "conditionals",
        "enumerations",
        "integers",
        "lists",
        "loops"
      ],
      "unlocked_by": "gigasecond",
      "uuid": "6a617ddb-04e3-451c-bb30-27ccd0be9125"
    },
    {
      "core": false,
      "difficulty": 5,
      "slug": "bob",
      "topics": [
        "booleans",
        "conditionals",
        "strings"
      ],
      "unlocked_by": "two-fer",
      "uuid": "34cd328c-cd96-492b-abd4-2b8716cdcd9a"
    },
    {
      "core": false,
      "difficulty": 5,
      "slug": "pascals-triangle",
      "topics": [
        "algorithms",
        "arrays",
        "exception_handling",
        "integers",
        "mathematics",
        "matrices"
      ],
      "unlocked_by": "matrix",
      "uuid": "d2a76905-1c8c-4b03-b4f7-4fbff19329f3"
    },
    {
      "core": false,
      "difficulty": 5,
      "slug": "bracket-push",
      "topics": [
        "stacks",
        "strings"
      ],
      "unlocked_by": "flatten-array",
      "uuid": "85aa50ac-0141-49eb-bc6f-62f3f7a97647"
    },
    {
      "core": false,
      "difficulty": 5,
      "slug": "series",
      "topics": [
        "conditionals",
        "lists",
        "loops",
        "strings",
        "type_conversion"
      ],
      "unlocked_by": "hamming",
      "uuid": "af80d7f4-c7d0-4d0b-9c30-09da120f6bb9"
    },
    {
      "core": false,
      "difficulty": 5,
      "slug": "atbash-cipher",
      "topics": [
        "cryptography",
        "security",
        "strings"
      ],
      "unlocked_by": "rotational-cipher",
      "uuid": "d36ce010-210f-4e9a-9d6c-cb933e0a59af"
    },
    {
      "core": false,
      "difficulty": 5,
      "slug": "grep",
      "topics": [
        "pattern_matching",
        "strings",
        "files",
        "filtering",
        "searching"
      ],
      "unlocked_by": "robot-name",
      "uuid": "9c15ddab-7b52-43d4-b38c-0bf635b363c3"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "alphametics",
      "topics": [
        "mathematics",
        "logic",
        "conditionals"
      ],
      "unlocked_by": "secret-handshake",
      "uuid": "0639a1f8-5af4-4877-95c1-5db8e97c30bf"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "spiral-matrix",
      "topics": [
        "arrays",
        "integers",
        "loops",
        "mathematics",
        "matrices"
      ],
      "unlocked_by": "matrix",
      "uuid": "163fcc6b-c054-4232-a88b-0aded846a6eb"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "roman-numerals",
      "topics": [
        "integers",
        "logic",
        "loops",
        "maps",
        "mathematics",
        "strings"
      ],
      "unlocked_by": "hamming",
      "uuid": "3e728cd4-5e5f-4c69-8a53-bc36d020fcdb"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "transpose",
      "topics": [
        "arrays",
        "lists",
        "loops",
        "matrices",
        "strings",
        "text_formatting"
      ],
      "unlocked_by": "matrix",
      "uuid": "57b76837-4610-466f-9373-d5c2697625f1"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "house",
      "topics": [
        "arrays",
        "conditionals",
        "loops",
        "strings",
        "text_formatting"
      ],
      "unlocked_by": "two-fer",
      "uuid": "6b51aca3-3451-4a64-ad7b-00b151d7548a"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "food-chain",
      "topics": [
        "arrays",
        "lists",
        "strings"
      ],
      "unlocked_by": "two-fer",
      "uuid": "dd3e6fd6-5359-4978-acd7-c39374cead4d"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "beer-song",
      "topics": [
        "conditionals",
        "loops",
        "strings",
        "text_formatting",
        "variables"
      ],
      "unlocked_by": "two-fer",
      "uuid": "56943095-de76-40bf-b42b-fa3e70f8df5e"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "queen-attack",
      "topics": [
        "arrays",
        "classes",
        "conditionals",
        "games",
        "mathematics",
        "matrices"
      ],
      "unlocked_by": "scrabble-score",
      "uuid": "5404109e-3ed9-4691-8eaf-af8b36024a44"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "etl",
      "topics": [
        "lists",
        "maps",
        "transforming"
      ],
      "unlocked_by": "word-count",
      "uuid": "76d28d97-75d3-47eb-bb77-3d347b76f1b6"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "grade-school",
      "topics": [
        "conditionals",
        "lists",
        "maps",
        "sorting",
        "strings"
      ],
      "unlocked_by": "word-count",
      "uuid": "b4af5da1-601f-4b0f-bfb8-4a381851090c"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "robot-simulator",
      "topics": [
        "classes",
        "enumerations",
        "logic",
        "loops"
      ],
      "unlocked_by": "secret-handshake",
      "uuid": "993bde9d-7774-4e7a-a381-9eee75f28ecb"
    },
    {
      "core": true,
      "difficulty": 6,
      "slug": "binary-search",
      "topics": [
        "recursion",
        "arrays",
        "searching",
        "generics"
      ],
      "unlocked_by": null,
      "uuid": "50136dc3-caf7-4fa1-b7bd-0cba1bea9176"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "minesweeper",
      "topics": [
        "conditionals",
        "games",
        "integers",
        "lists",
        "matrices",
        "strings"
      ],
      "unlocked_by": "scrabble-score",
      "uuid": "416a1489-12af-4593-8540-0f55285c96b4"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "wordy",
      "topics": [
        "exception_handling",
        "integers",
        "logic",
        "parsing",
        "pattern_matching",
        "regular_expressions",
        "strings",
        "transforming"
      ],
      "unlocked_by": "secret-handshake",
      "uuid": "3310a3cd-c0cb-45fa-8c51-600178be904a"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "all-your-base",
      "topics": [
        "arrays",
        "conditionals",
        "exception_handling",
        "integers",
        "loops",
        "mathematics"
      ],
      "unlocked_by": "saddle-points",
      "uuid": "f7c2e4b5-1995-4dfe-b827-c9aff8ac5332"
    },
    {
      "core": true,
      "difficulty": 6,
      "slug": "bank-account",
      "topics": [
        "concurrency",
        "exception_handling",
        "integers"
      ],
      "unlocked_by": null,
      "uuid": "a242efc5-159d-492b-861d-12a1459fb334"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "bowling",
      "topics": [
        "conditionals",
        "exception_handling",
        "games",
        "integers",
        "mathematics"
      ],
      "unlocked_by": "scrabble-score",
      "uuid": "4b3f7771-c642-4278-a3d9-2fb958f26361"
    },
    {
      "core": true,
      "difficulty": 6,
      "slug": "linked-list",
      "topics": [
        "algorithms",
        "generics",
        "lists"
      ],
      "unlocked_by": null,
      "uuid": "7ba5084d-3b75-4406-a0d7-87c26387f9c0"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "tournament",
      "topics": [
        "loops",
        "maps",
        "parsing",
        "sorting",
        "text_formatting"
      ],
      "unlocked_by": "matrix",
      "uuid": "486d342e-c834-40fc-b691-a4dab3f790da"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "parallel-letter-frequency",
      "topics": [
        "concurrency",
        "maps",
        "strings"
      ],
      "unlocked_by": "bank-account",
      "uuid": "38a405e8-619d-400f-b53c-2f06461fdf9d"
    },
    {
      "core": false,
      "difficulty": 6,
      "slug": "rail-fence-cipher",
      "topics": [
        "strings",
        "loops",
        "conditionals"
      ],
      "unlocked_by": "rotational-cipher",
      "uuid": "6e4ad4ed-cc02-4132-973d-b9163ba0ea3d"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "two-bucket",
      "topics": [
        "algorithms",
        "loops",
        "conditionals",
        "mathematics"
      ],
      "unlocked_by": "triangle",
      "uuid": "210bf628-b385-443b-8329-3483cc6e8d7e"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "anagram",
      "topics": [
        "arrays",
        "conditionals",
        "equality",
        "lists",
        "loops",
        "strings"
      ],
      "unlocked_by": "hello-world",
      "uuid": "fb10dc2f-0ba1-44b6-8365-5e48e86d1283"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "sublist",
      "topics": [
        "enumeration",
        "generics",
        "lists",
        "loops",
        "searching"
      ],
      "unlocked_by": "linked-list",
      "uuid": "d2aedbd7-092a-43d0-8a5e-ae3ebd5b9c7f"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "word-search",
      "topics": [
        "games",
        "logic",
        "matrices",
        "pattern_matching",
        "searching",
        "strings"
      ],
      "unlocked_by": "scrabble-score",
      "uuid": "b53bde52-cb5f-4d43-86ec-18aa509d62f9"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "simple-linked-list",
      "topics": [
        "algorithms",
        "exception_handling",
        "generics",
        "lists"
      ],
      "unlocked_by": "linked-list",
      "uuid": "e3e5ffe5-cfc1-467e-a28a-da0302130144"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "binary-search-tree",
      "topics": [
        "generics",
        "graphs",
        "searching",
        "sorting",
        "trees"
      ],
      "unlocked_by": "binary-search",
      "uuid": "0a2d18aa-7b5e-4401-a952-b93d2060694f"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "meetup",
      "topics": [
        "conditionals",
        "dates",
        "enumerations",
        "loops"
      ],
      "unlocked_by": "gigasecond",
      "uuid": "602511d5-7e89-4def-b072-4dd311816810"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "crypto-square",
      "topics": [
        "cryptography",
        "lists",
        "mathematics",
        "security",
        "strings",
        "text_formatting"
      ],
      "unlocked_by": "rotational-cipher",
      "uuid": "162bebdc-9bf2-43c0-8460-a91f5fc16147"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "markdown",
      "topics": [
        "strings",
        "conditionals",
        "pattern_matching",
        "refactoring"
      ],
      "unlocked_by": "scrabble-score",
      "uuid": "cc18f2e5-4e36-47d6-aa60-8ca5ff54019a"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "poker",
      "topics": [
        "games",
        "parsing",
        "sorting"
      ],
      "unlocked_by": "scrabble-score",
      "uuid": "57eeac00-741c-4843-907a-51f0ac5ea4cb"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "clock",
      "topics": [
        "equality",
        "integers",
        "logic",
        "object_oriented_programming",
        "strings",
        "time"
      ],
      "unlocked_by": "saddle-points",
      "uuid": "97c8fcd4-85b6-41cb-9de2-b4e1b4951222"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "zipper",
      "topics": [
        "integer",
        "nodes",
        "tree",
        "links"
      ],
      "unlocked_by": "linked-list",
      "uuid": "25d2c7a5-1ec8-464a-b3de-ad1b27464ef1"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "go-counting",
      "topics": [
        "algorithms",
        "loops",
        "conditionals",
        "games"
      ],
      "unlocked_by": "scrabble-score",
      "uuid": "2e760ae2-fadd-4d31-9639-c4554e2826e9"
    },
    {
      "core": false,
      "difficulty": 7,
      "slug": "dominoes",
      "topics": [
        "games",
        "algorithms",
        "lists",
        "exception_handling"
      ],
      "unlocked_by": "scrabble-score",
      "uuid": "8e3cb20e-623b-4b4d-8a91-d1a51c0911b5"
    },
    {
      "core": false,
      "difficulty": 8,
      "slug": "ocr-numbers",
      "topics": [
        "exception_handling",
        "lists",
        "loops",
        "parsing",
        "strings"
      ],
      "unlocked_by": "robot-name",
      "uuid": "5cbc6a67-3a53-4aad-ae68-ff469525437f"
    },
    {
      "core": false,
      "difficulty": 8,
      "slug": "circular-buffer",
      "topics": [
        "classes",
        "exception_handling",
        "queues"
      ],
      "unlocked_by": "linked-list",
      "uuid": "626dc25a-062c-4053-a8c1-788e4dc44ca0"
    },
    {
      "core": false,
      "difficulty": 8,
      "slug": "rectangles",
      "topics": [
        "arrays",
        "logic",
        "pattern_recognition",
        "strings"
      ],
      "unlocked_by": "robot-name",
      "uuid": "64cda115-919a-4eef-9a45-9ec5d1af98cc"
    },
    {
      "core": false,
      "difficulty": 8,
      "slug": "book-store",
      "topics": [
        "algorithms",
        "floating_point_numbers",
        "integers",
        "lists",
        "mathematics"
      ],
      "unlocked_by": "flatten-array",
      "uuid": "e5f05d00-fe5b-4d78-b2fa-934c1c9afb32"
    },
    {
      "core": false,
      "difficulty": 8,
      "slug": "diffie-hellman",
      "topics": [
        "algorithms",
        "integers",
        "transforming"
      ],
      "unlocked_by": "linked-list",
      "uuid": "9b191b2f-b1a4-4c0e-b911-36666bff614d"
    },
    {
      "core": false,
      "difficulty": 8,
      "slug": "simple-cipher",
      "topics": [
        "cryptography",
        "exception_handling",
        "mathematics",
        "randomness",
        "security",
        "strings"
      ],
      "unlocked_by": "rotational-cipher",
      "uuid": "f654831f-c34b-44f5-9dd5-054efbb486f2"
    },
    {
      "core": false,
      "difficulty": 8,
      "slug": "complex-numbers",
      "topics": [
        "floating_point_numbers",
        "mathematics"
      ],
      "unlocked_by": "triangle",
      "uuid": "52d11278-0d65-4b5b-b387-1374fced3243"
    },
    {
      "core": false,
      "difficulty": 8,
      "slug": "rational-numbers",
      "topics": [
        "floating_point_numbers",
        "mathematics",
        "algorithms"
      ],
      "unlocked_by": "triangle",
      "uuid": "50ed54ce-3047-4590-9fda-0a7e9aeeba30"
    },
    {
      "core": false,
      "difficulty": 8,
      "slug": "list-ops",
      "topics": [
        "filtering",
        "functional_programming",
        "generics",
        "lists",
        "loops"
      ],
      "unlocked_by": "linked-list",
      "uuid": "a9836565-5c39-4285-b83a-53408be36ccc"
    },
    {
      "core": false,
      "difficulty": 8,
      "slug": "change",
      "topics": [
        "algorithms",
        "exception_handling",
        "integers",
        "lists"
      ],
      "unlocked_by": "flatten-array",
      "uuid": "bac1f4bc-eea9-43c1-8e95-097347f5925e"
    },
    {
      "core": false,
      "difficulty": 8,
      "slug": "palindrome-products",
      "topics": [
        "conditionals",
        "integers",
        "lists",
        "loops",
        "maps",
        "mathematics"
      ],
      "unlocked_by": "saddle-points",
      "uuid": "873c05de-b5f5-4c5b-97f0-d1ede8a82832"
    },
    {
      "core": false,
      "difficulty": 9,
      "slug": "pythagorean-triplet",
      "topics": [
        "integer",
        "lists",
        "logic",
        "mathematics"
      ],
      "unlocked_by": "triangle",
      "uuid": "88505f95-89e5-4a08-8ed2-208eb818cdf1"
    },
    {
      "core": false,
      "difficulty": 9,
      "slug": "forth",
      "topics": [
        "exception_handling",
        "lists",
        "logic",
        "parsing",
        "stacks",
        "strings"
      ],
      "unlocked_by": "secret-handshake",
      "uuid": "f0c0316d-3fb5-455e-952a-91161e7fb298"
    },
    {
      "core": false,
      "difficulty": 10,
      "slug": "custom-set",
      "topics": [
        "equality",
        "generics",
        "sets"
      ],
      "unlocked_by": "linked-list",
      "uuid": "377fe38b-08ad-4f3a-8118-a43c10f7b9b2"
    },
    {
      "deprecated": true,
      "slug": "accumulate",
      "uuid": "e58c29d2-80a7-40ef-bed0-4a184ae35f34"
    },
    {
      "deprecated": true,
      "slug": "binary",
      "uuid": "9ea6e0fa-b91d-4d17-ac8f-6d2dc30fdd44"
    },
    {
      "deprecated": true,
      "slug": "hexadecimal",
      "uuid": "6fe53a08-c123-465d-864a-ef18217203c4"
    },
    {
      "deprecated": true,
      "slug": "octal",
      "uuid": "14a29e82-f9b1-4662-b678-06992e306c01"
    },
    {
      "deprecated": true,
      "slug": "strain",
      "uuid": "2d195cd9-1814-490a-8dd6-a2c676f1d4cd"
    },
    {
      "deprecated": true,
      "slug": "trinary",
      "uuid": "ee3a8abe-6b19-4b47-9cf6-4d39ae915fb7"
    }
  ],
  "foregone": [
    "leap",
    "grains",
    "say"
  ],
  "language": "Java",
  "solution_pattern": "reference"
}