Kotlin學習筆記（十五）函數操作符（順序操作符）

1.reverse

反轉

package com.example.kotlin01

val list = listOf(1,2,3,5,6,7)
fun main() {
    val result = list.reversed()
    println(result)

}

[7, 6, 5, 3, 2, 1]

2.sort

排序，從小到大

package com.example.kotlin01

val list = listOf(1,2,3,5,6,7)
fun main() {
    val result = list.sorted()
    println(result)
}

[1, 2, 3, 5, 6, 7]

3.sortBy

根據某個函數處理後在排序，從小到大

package com.example.kotlin01

val list1 = listOf(2, 4, 1, 9, 5, 10)
fun main() {
    val result = list1.sortedBy { it/-1 }
    println(result)
}

[10, 9, 5, 4, 2, 1]

4.sortDescending

排序，從大到小

package com.example.kotlin01

val list1 = listOf(2, 4, 1, 9, 5, 10)
fun main() {
    val result = list1.sortedDescending()
    println(result)
}

[10, 9, 5, 4, 2, 1]

5.sortDescendingBy

根據某個函數處理後在排序，從大到小

package com.example.kotlin01

val list1 = listOf(2, 4, 1, 9, 5, 10)
fun main() {
    val result = list1.sortedByDescending { it / -1 }
    println(result)
}

[1, 2, 4, 5, 9, 10]