Added Square and Equilateral Triangle classes

SwiftyFox.playground/Contents.swift

@@ -27,13 +27,68 @@ func calcStats(scores: [Int]) -> (min: Int, max: Int, sum: Int) {
 let stats = calcStats(scores: [5, 3, 100, 3, 9])
 let sum = stats.sum // 120
 
-class Shape {
+class NamedShape {
     var numberOfSides = 0
+    var name: String
+    
+    init(name: String = "Heptagon") {
+        self.name = name
+    }
+    
     func simpleDescription() -> String {
         return "A shape with \(numberOfSides) sides."
     }
 }
 
-var shape = Shape()
+class Square: NamedShape {
+    var sideLength: Double
+    
+    init(sideLength: Double, name: String = "Square") {
+        self.sideLength = sideLength
+        super.init(name: name)
+    }
+    
+    func area() -> Double {
+        return sideLength * sideLength
+    }
+    
+    override func simpleDescription() -> String {
+        return "A Square with \(numberOfSides) sides."
+    }
+}
+
+class EquilateralTriangle: NamedShape {
+    var sideLength: Double
+    
+    var perimeter: Double {
+        get {
+            return 3.0 * sideLength
+        }
+        
+        set {
+            sideLength = newValue / 3.0
+        }
+    }
+    
+    init(sideLength: Double, name: String = "Square") {
+        self.sideLength = sideLength
+        super.init(name: name)
+        numberOfSides = 3
+    }
+    
+    func area() -> Double {
+        return sideLength * sideLength
+    }
+    
+    override func simpleDescription() -> String {
+        return "A Equilateral Triangle with \(numberOfSides) sides."
+    }
+}
+
+var shape = NamedShape()
 shape.numberOfSides = 7
-var shapeDesc = shape.simpleDescription()
+shape.simpleDescription()
+
+var square = Square(sideLength: 5.2)
+square.area()
+square.simpleDescription()