var name = "hello"

for (n <- name)

{

　　println(n)

}

  def main(args: Array[String]): Unit = {

    for (a <- 1 to 10) {

      for (b <- 1 to 10) {

        if (a == b) {

          println("a = " + a + ", b = " + b)

        }

      }

    }

    
    //嵌套循环的等价新写法
    for (a <- 1 to 10; b <- 1 to 10 if a == b) {
      ...
    }

    val arr = Array[Int](1,2,3,4,5)

    for(elem <- arr) {

      println(elem1)

    }

   }

    val arr = Array[Int](1,2,3,4,5)

    val arr1 = new Array[Int](arr.length)

    for (index <- 0 until arr.length) {

      arr1(index) = arr(index) + 10

    }

    println(arr1.toBuffer)

    val arr = Array[Int](1,2,3,4,5)

    val ret = for (a <- arr) yield a + 10

    println(ret.toBuffer)

  def main(args: Array[String]): Unit = {

    val x = 1

    val y = if (x > 0) 1 else -1

    println(y)

    val m = if (x > 2) 1

    println(m)

    val n = if (x > 2) 1 else ()

    println(n)

    val k = if (x < 0) 0 else if (x >= 1) 1 else -1

    print(k)

   }

  def ml(a: Int, b: Int): Unit = {

    println("hello, " + (a+b))

  }

  def main(args: Array[String]): Unit = {
    // 1.匿名函数

    val f1 = (a:Int, b: Int) => a + b

    println(f1(10, 20))

    // 2.普通函数

    ml(10,20)

  }