Add nth-prime (#143)

config.json

@@ -237,6 +237,14 @@
         "prerequisites": [],
         "difficulty": 2
       },
+      {
+        "slug": "nth-prime",
+        "name": "Nth Prime",
+        "uuid": "8cf8f184-0b62-4a2d-ba0f-042d069e4d1d",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 2
+      },
       {
         "slug": "nucleotide-count",
         "name": "Nucleotide Count",

exercises/practice/nth-prime/.docs/instructions.md

@@ -0,0 +1,7 @@
+# Instructions
+
+Given a number n, determine what the nth prime is.
+
+By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13.
+
+If your language provides methods in the standard library to deal with prime numbers, pretend they don't exist and implement them yourself.

exercises/practice/nth-prime/.meta/config.json

@@ -0,0 +1,22 @@
+{
+  "authors": [
+    "BNAndras"
+  ],
+  "files": {
+    "solution": [
+      "src/nth-prime.art"
+    ],
+    "test": [
+      "tests/test-nth-prime.art"
+    ],
+    "example": [
+      ".meta/src/example.art"
+    ],
+    "invalidator": [
+      "tester.art"
+    ]
+  },
+  "blurb": "Given a number n, determine what the nth prime is.",
+  "source": "A variation on Problem 7 at Project Euler",
+  "source_url": "https://projecteuler.net/problem=7"
+}

exercises/practice/nth-prime/.meta/src/example.art

@@ -0,0 +1,12 @@
+prime: function [number][
+    if number < 1 -> return false
+    if one? number -> return 2
+
+    result: 1
+    current: 1
+    while [current < number] [
+        add 'result 2
+        if prime? result -> inc 'current
+    ] 
+    result 
+]

exercises/practice/nth-prime/.meta/tests.toml

@@ -0,0 +1,25 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[75c65189-8aef-471a-81de-0a90c728160c]
+description = "first prime"
+
+[2c38804c-295f-4701-b728-56dea34fd1a0]
+description = "second prime"
+
+[56692534-781e-4e8c-b1f9-3e82c1640259]
+description = "sixth prime"
+
+[fce1e979-0edb-412d-93aa-2c744e8f50ff]
+description = "big prime"
+
+[bd0a9eae-6df7-485b-a144-80e13c7d55b2]
+description = "there is no zeroth prime"

exercises/practice/nth-prime/src/nth-prime.art

@@ -0,0 +1,3 @@
+prime: function [number][
+    panic "Please implement the prime function"
+]

exercises/practice/nth-prime/tester.art

@@ -0,0 +1,3 @@
+import {unitt}! 
+
+runTests.failFast findTests "tests"

exercises/practice/nth-prime/tests/test-nth-prime.art

@@ -0,0 +1,29 @@
+import {unitt}!
+import {src/nth-prime}!
+
+suite "Nth Prime" [
+    test "first prime" [
+        result: prime 1
+        assert -> 2 = result
+    ]
+
+    test.skip "second prime" [
+        result: prime 2
+        assert -> 3 = result
+    ]
+
+    test.skip "sixth prime" [
+        result: prime 6
+        assert -> 13 = result
+    ]
+
+    test.skip "big prime" [
+        result: prime 10001
+        assert -> 104743 = result
+    ]
+
+    test.skip "there is no zeroth prime" [
+        result: prime 0
+        assert -> false = result
+    ]
+]