Add square-root exercise (#374)

* Add square-root exercise

* Compare numbers using =

config.json

@@ -393,6 +393,17 @@
         "prerequisites": [],
         "difficulty": 2
       },
+      {
+        "slug": "square-root",
+        "name": "Square Root",
+        "uuid": "d74d3b6d-43db-4f46-a25d-b1a86df3fb47",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 2,
+        "topics": [
+          "math"
+        ]
+      },
       {
         "slug": "sublist",
         "name": "Sublist",

exercises/practice/square-root/.docs/instructions.md

@@ -0,0 +1,13 @@
+# Instructions
+
+Given a natural radicand, return its square root.
+
+Note that the term "radicand" refers to the number for which the root is to be determined.
+That is, it is the number under the root symbol.
+
+Check out the Wikipedia pages on [square root][square-root] and [methods of computing square roots][computing-square-roots].
+
+Recall also that natural numbers are positive real whole numbers (i.e. 1, 2, 3 and up).
+
+[square-root]: https://en.wikipedia.org/wiki/Square_root
+[computing-square-roots]: https://en.wikipedia.org/wiki/Methods_of_computing_square_roots

exercises/practice/square-root/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "keiravillekode"
+  ],
+  "files": {
+    "solution": [
+      "square-root.el"
+    ],
+    "test": [
+      "square-root-test.el"
+    ],
+    "example": [
+      ".meta/example.el"
+    ]
+  },
+  "blurb": "Given a natural radicand, return its square root.",
+  "source": "wolf99",
+  "source_url": "https://github.com/exercism/problem-specifications/pull/1582"
+}

exercises/practice/square-root/.meta/example.el

@@ -0,0 +1,15 @@
+;;; square-root.el --- Square Root (exercism)  -*- lexical-binding: t; -*-
+
+;;; Commentary:
+
+;;; Code:
+
+(require 'cl-lib)
+
+(defun square-root (radicand)
+  (cl-loop for num from 0
+    until (<= radicand (* num num))
+    finally return num))
+
+(provide 'square-root)
+;;; square-root.el ends here

exercises/practice/square-root/.meta/tests.toml

@@ -0,0 +1,28 @@
+# 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.
+
+[9b748478-7b0a-490c-b87a-609dacf631fd]
+description = "root of 1"
+
+[7d3aa9ba-9ac6-4e93-a18b-2e8b477139bb]
+description = "root of 4"
+
+[6624aabf-3659-4ae0-a1c8-25ae7f33c6ef]
+description = "root of 25"
+
+[93beac69-265e-4429-abb1-94506b431f81]
+description = "root of 81"
+
+[fbddfeda-8c4f-4bc4-87ca-6991af35360e]
+description = "root of 196"
+
+[c03d0532-8368-4734-a8e0-f96a9eb7fc1d]
+description = "root of 65025"

exercises/practice/square-root/square-root-test.el

@@ -0,0 +1,36 @@
+;;; square-root-test.el --- Tests for Square Root (exercism)  -*- lexical-binding: t; -*-
+
+;;; Commentary:
+
+;;; Code:
+
+(load-file "square-root.el")
+(declare-function square-root "square-root.el" (radicand))
+
+
+(ert-deftest root-of-1 ()
+  (should (= 1 (square-root 1))))
+
+
+(ert-deftest root-of-4 ()
+  (should (= 2 (square-root 4))))
+
+
+(ert-deftest root-of-25 ()
+  (should (= 5 (square-root 25))))
+
+
+(ert-deftest root-of-81 ()
+  (should (= 9 (square-root 81))))
+
+
+(ert-deftest root-of-196 ()
+  (should (= 14 (square-root 196))))
+
+
+(ert-deftest root-of-65025 ()
+  (should (= 255 (square-root 65025))))
+
+
+(provide 'square-root-test)
+;;; square-root-test.el ends here

exercises/practice/square-root/square-root.el

@@ -0,0 +1,13 @@
+;;; square-root.el --- Square Root (exercism)  -*- lexical-binding: t; -*-
+
+;;; Commentary:
+
+;;; Code:
+
+
+(defun square-root (radicand)
+  (error "Delete this S-Expression and write your own implementation"))
+
+
+(provide 'square-root)
+;;; square-root.el ends here