Swift和Java控制流比较

1. Swift中for in循环和Java中foreach很类似，都可以简化对集合的遍历操作。

Swift语法：

  for index in 1...5{
            print("the index is \(index)")
        }

        let base = 3
        let power = 3
        var answer = 1
        for _ in 1...power {
            answer *= base
      }
        print("\(base) to the power of \(power) is \(answer)")
        // 输出 "3 to the power of 10 is 59049"

Java语法如下：

      ArrayList<String> array = new ArrayList<String>();
        array.add("a");
        array.add("b");
        array.add("c");
        array.add("d");
        for(String item: array){
            System.out.println(item);
        }