Add tasks for all the new languages

Task/Arithmetic-Complex/Swift/arithmetic-complex-1.swift

@@ -0,0 +1,45 @@
+public struct Complex {
+
+    public let real : Double
+    public let imaginary : Double
+
+    public init(real inReal:Double, imaginary inImaginary:Double) {
+        real = inReal
+        imaginary = inImaginary
+    }
+
+    public static var i : Complex = Complex(real:0, imaginary: 1)
+    public static var zero : Complex = Complex(real: 0, imaginary: 0)
+
+    public var negate : Complex {
+        return Complex(real: -real, imaginary: -imaginary)
+    }
+
+    public var invert : Complex {
+        let d = (real*real + imaginary*imaginary)
+        return Complex(real: real/d, imaginary: -imaginary/d)
+    }
+
+    public var conjugate : Complex {
+        return Complex(real: real, imaginary: -imaginary)
+    }
+
+}
+public func + (left: Complex, right: Complex) -> Complex {
+
+    return Complex(real: left.real+right.real, imaginary: left.imaginary+right.imaginary)
+}
+public func * (left: Complex, right: Complex) -> Complex {
+
+    return Complex(real: left.real*right.real - left.imaginary*right.imaginary,
+        imaginary: left.real*right.imaginary+left.imaginary*right.real)
+}
+public prefix func - (right:Complex) -> Complex {
+    return right.negate
+}
+
+// Checking equality is almost necessary for a struct of this type  to be useful
+extension Complex : Equatable {}
+public func == (left:Complex, right:Complex) -> Bool {
+    return left.real == right.real && left.imaginary == right.imaginary
+}

Task/Arithmetic-Complex/Swift/arithmetic-complex-2.swift

@@ -0,0 +1,24 @@
+extension Complex : CustomStringConvertible {
+
+    public var description : String {
+
+        guard real != 0 || imaginary != 0 else { return "0" }
+
+        let rs : String = real != 0 ? "\(real)" : ""
+        let iS : String
+        let sign : String
+        let iSpace = real != 0 ? " " : ""
+        switch imaginary {
+        case let i where i < 0:
+            sign = "-"
+            iS = i == -1 ? "i" : "\(-i)i"
+        case let i where i > 0:
+            sign = real != 0 ? "+" : ""
+            iS = i == 1 ? "i" : "\(i)i"
+        default:
+            sign = ""
+            iS = ""
+        }
+        return "\(rs)\(iSpace)\(sign)\(iSpace)\(iS)"
+    }
+}

Task/Arithmetic-Complex/Swift/arithmetic-complex-3.swift

@@ -0,0 +1,10 @@
+public func - (left:Complex, right:Complex) -> Complex {
+    return left + -right
+}
+
+public func / (divident:Complex, divisor:Complex) -> Complex {
+    let rc = divisor.conjugate
+    let num = divident * rc
+    let den = divisor * rc
+    return Complex(real: num.real/den.real, imaginary: num.imaginary/den.real)
+}