object day01 {
//main函数
def main(args: Array[String]): Unit = {
//简单输出
val name: String = "hello scala"
println(name)
//循环1
var a = 0
for (a <- 3 to 6) {
println("a:" + a)
}
//循环2
val list = List(2, 3, 4, 5, 6)
list.foreach(i => {
println("list:" + i)
})
//循环3
for (j <- 1 until list.length) {
println("list2:" + list(j))
}
//循环4
var n = 0;
for (n <- list) {
println("list3:" + n)
}
//九九乘法表
for (i <- 1 to 9) {
for (j <- 1 to i) {
print(j + "*" + i + "=" + (j * i) + "\t")
}
println()
}
//自定义函数
add(8, 7)
val q = "abc"
q.getClass
var w = "abc"
w = "qwe"
val e = "hello"
println("获取字符串“Hello”的首字符" + e.charAt(0))
println(e(0))
println(e.head)
println(e.substring(0,1))
println(e.take(1))
println("获取字符串“Hello”的尾字符" + e.charAt(e.length - 1))
println(e.last)
println(e.reverse(0))
println(e.reverse.head)
println(e.substring(e.length-1,e.length()))
println(e.takeRight(1))
//,求出每个班的平均分和所有班级的平均分?
val class1 = List(88, 89, 93, 95, 100)
val class2 = List(91, 93, 96, 95, 99)
val class3 = List(87, 98, 93, 95, 91)
var sum1 = 0
var sum2 = 0
var sum3 = 0
var y = 0
for (i <- 0 until 5) {
println("请输入班级1的一位学生成绩")
y = Console.readLine().toInt //还可以 readInt;
sum1 += y
}
println("班级一平均分:" + sum1 / 5)
for (i <- 0 until 5) {
println("请输入班级2的一位学生成绩")
y = Console.readLine().toInt
sum2 += y
}
println("班级二平均分:" + sum2 / 5)
for (i <- 0 until 5) {
println("请输入班级3的一位学生成绩")
y = Console.readLine().toInt
sum3 += y
}
println("班级三平均分:" + sum3 / 5)
println("所有班级的平均分:" + (sum1 + sum2 + sum3) / 15)
for (i <- 1 to 9) {
for (j <- 1 to i) {
print(j + "*" + i + "=" + j * i + "\t")
}
print("\n")
}
var sum = 0
var u: Boolean = true
for (i <- 1 to 100 if u == true) {
sum = sum + i
if (sum > 20) {
println("i=" + i)
u = false
}
}
lazy val haha=(print("lanjiazai"))
//只有调用haha 才能输出
haha
//差值器
//1.s差值器
val name1:String="cat"
println(s"she is name is ${name1}")
//2.f差值器
val height=1.23568
println(f"身高是${height}%.2f")
//3.raw差值器
//没有使用raw
println("a\nb\n\tc")
//使用的效果
println(raw"a\nb\n\tc")
val str = Console.readLine()
println(str)
}
def add(a: Int, b: Int): Int = {
println(a + "+" + b + "=" + (a + b))
a + b
}
}