1、没有了亲切的C语言for循环，先上代码

         var hhArr:Array =[1,2,423,12,123435,2,123,12,234,563,412,3,34,12,4,45,1234,6,23,41,35,4652,34,15,234,124,21,123,23,123,123,12,3,23,4,536,23,124,5,1,24,345,124,5,1234,45,723,4,124,234,124,12,3,123,123,234,4567,546,45,67,456]

        var stratTime = CACurrentMediaTime()

        //forin 遍历（只有value）
        for num in hhArr {

            print(num)
        }
        var duration:String = String(format: "%.7f", (CACurrentMediaTime() - stratTime))
        print("forin执行时间\(duration) \n")
        stratTime = CACurrentMediaTime()


        //Range 遍历 (index，value)
        for index in 0..<hhArr.count {

            print("index:\(index),value:\(hhArr[index])");
        }
        duration = String(format: "%.7f", (CACurrentMediaTime() - stratTime))
        print("Range执行时间\(duration) \n")
        stratTime = CACurrentMediaTime()

        //enmerated 遍历 (offset，value)
        for num in hhArr.enumerated() {
            let rs:String = "index:\(num.offset) value:\(num.element)";
            print(rs);
        }
        duration = String(format: "%.7f", (CACurrentMediaTime() - stratTime))
        print("enmerated执行时间\(duration) \n")
        stratTime = CACurrentMediaTime()

        //enmerated 赋值遍历 (index，value)
        for (index,value) in hhArr.enumerated() {

            print("index:\(index),value:\(value)");
        }
        duration = String(format: "%.7f", (CACurrentMediaTime() - stratTime))
        print("enmerated赋值执行时间\(duration) \n")
        stratTime = CACurrentMediaTime()


        //enmerated 反向遍历 (index，value)
        for (index,value) in hhArr.enumerated().reversed() {

            print("index:\(index),value:\(value)");
        }
        duration = String(format: "%.7f", (CACurrentMediaTime() - stratTime))
        print("enmerated倒序执行时间\(duration) \n")
        stratTime = CACurrentMediaTime()