[New exercise] Add square roots

config.json

@@ -551,6 +551,18 @@
           "randomness"
         ]
       },
+      {
+        "slug": "square-root",
+        "name": "Square Root",
+        "uuid": "e277811f-3dbc-48c5-ae96-8c14c68564e2",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 2,
+        "topics": [
+          "math",
+          "integers"
+        ]
+      },
       {
         "slug": "binary-search",
         "name": "Binary Search",

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

@@ -0,0 +1,18 @@
+# Instructions
+
+Your task is to calculate the square root of a given number.
+
+- Try to avoid using the pre-existing math libraries of your language.
+- As input you'll be given a positive whole number, i.e. 1, 2, 3, 4…
+- You are only required to handle cases where the result is a positive whole number.
+
+Some potential approaches:
+
+- Linear or binary search for a number that gives the input number when squared.
+- Successive approximation using Newton's or Heron's method.
+- Calculating one digit at a time or one bit at a time.
+
+You can check out the Wikipedia pages on [integer square root][integer-square-root] and [methods of computing square roots][computing-square-roots] to help with choosing a method of calculation.
+
+[integer-square-root]: https://en.wikipedia.org/wiki/Integer_square_root
+[computing-square-roots]: https://en.wikipedia.org/wiki/Methods_of_computing_square_roots

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

@@ -0,0 +1,10 @@
+# Introduction
+
+We are launching a deep space exploration rocket and we need a way to make sure the navigation system stays on target.
+
+As the first step in our calculation, we take a target number and find its square root (that is, the number that when multiplied by itself equals the target number).
+
+The journey will be very long.
+To make the batteries last as long as possible, we had to make our rocket's onboard computer very power efficient.
+Unfortunately that means that we can't rely on fancy math libraries and functions, as they use more power.
+Instead we want to implement our own square root calculation.

exercises/practice/square-root/.meta/Sources/SquareRoot/SquareRootExample.swift

@@ -0,0 +1,27 @@
+enum SquareRootError: Error {
+  case negativeInput
+}
+
+struct SquareRoot {
+  static func squareRoot(_ n: Int) throws -> Int {
+    guard n >= 0 else {
+      throw SquareRootError.negativeInput
+    }
+    if n == 0 || n == 1 {
+      return n
+    }
+    var low = 1
+    var high = n
+    var result = 1
+    while low <= high {
+      let mid = low + (high - low) / 2
+      if mid <= n / mid {
+        result = mid
+        low = mid + 1
+      } else {
+        high = mid - 1
+      }
+    }
+    return result
+  }
+}

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

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "Sencudra"
+  ],
+  "files": {
+    "solution": [
+      "Sources/SquareRoot/SquareRoot.swift"
+    ],
+    "test": [
+      "Tests/SquareRootTests/SquareRootTests.swift"
+    ],
+    "example": [
+      ".meta/Sources/SquareRoot/SquareRootExample.swift"
+    ]
+  },
+  "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/template.swift

@@ -0,0 +1,22 @@
+import Testing
+import Foundation
+
+@testable import {{ exercise|camelCase }}
+
+let RUNALL = Bool(ProcessInfo.processInfo.environment["RUNALL", default: "false"]) ?? false
+
+@Suite struct {{ exercise|camelCase }}Tests {
+    {% for case in cases %}
+    {% if forloop.first -%}
+        @Test("{{ case.description }}")
+    {% else -%}
+        @Test("{{ case.description }}", .enabled(if: RUNALL))
+    {% endif -%}
+    func test{{ case.description|camelCase }}() {
+        #expect(throws: Never.self) {
+            let actual = try {{ exercise|camelCase }}.squareRoot({{ case.input.radicand }})
+            #expect(actual == {{ case.expected }})
+        }
+    }
+    {% endfor -%}
+}

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/Package.swift

@@ -0,0 +1,21 @@
+// swift-tools-version:6.0
+
+import PackageDescription
+
+let package = Package(
+  name: "SquareRoot",
+  products: [
+    .library(
+      name: "SquareRoot",
+      targets: ["SquareRoot"])
+  ],
+  dependencies: [],
+  targets: [
+    .target(
+      name: "SquareRoot",
+      dependencies: []),
+    .testTarget(
+      name: "SquareRootTests",
+      dependencies: ["SquareRoot"]),
+  ]
+)

exercises/practice/square-root/Sources/SquareRoot/SquareRoot.swift

@@ -0,0 +1,3 @@
+struct SquareRoot {
+   // Write your code for the 'SquareRoot' exercise here.
+}

exercises/practice/square-root/Tests/SquareRootTests/SquareRootTests.swift

@@ -0,0 +1,57 @@
+import Foundation
+import Testing
+
+@testable import SquareRoot
+
+let RUNALL = Bool(ProcessInfo.processInfo.environment["RUNALL", default: "false"]) ?? false
+
+@Suite struct SquareRootTests {
+
+  @Test("root of 1")
+  func testRootOf1() {
+    #expect(throws: Never.self) {
+      let actual = try SquareRoot.squareRoot(1)
+      #expect(actual == 1)
+    }
+  }
+
+  @Test("root of 4", .enabled(if: RUNALL))
+  func testRootOf4() {
+    #expect(throws: Never.self) {
+      let actual = try SquareRoot.squareRoot(4)
+      #expect(actual == 2)
+    }
+  }
+
+  @Test("root of 25", .enabled(if: RUNALL))
+  func testRootOf25() {
+    #expect(throws: Never.self) {
+      let actual = try SquareRoot.squareRoot(25)
+      #expect(actual == 5)
+    }
+  }
+
+  @Test("root of 81", .enabled(if: RUNALL))
+  func testRootOf81() {
+    #expect(throws: Never.self) {
+      let actual = try SquareRoot.squareRoot(81)
+      #expect(actual == 9)
+    }
+  }
+
+  @Test("root of 196", .enabled(if: RUNALL))
+  func testRootOf196() {
+    #expect(throws: Never.self) {
+      let actual = try SquareRoot.squareRoot(196)
+      #expect(actual == 14)
+    }
+  }
+
+  @Test("root of 65025", .enabled(if: RUNALL))
+  func testRootOf65025() {
+    #expect(throws: Never.self) {
+      let actual = try SquareRoot.squareRoot(65025)
+      #expect(actual == 255)
+    }
+  }
+}