跳至主要内容

[pkg] sort

sort

常用方法​

func main() {
  nums := []int{45, 20, 35, 30, 75, 60, 50, 25}
  sort.Ints(nums)
  fmt.Println(nums) //  [20 25 30 35 45 50 60 75]

  fmt.Println(sort.SearchInts(nums, 30)) // 2

 // can get the index even if not found
  fmt.Println(sort.SearchInts(nums, 22)) // 1
  fmt.Println(sort.SearchInts(nums, 40)) // 4
  fmt.Println(sort.SearchInts(nums, 88)) // 8

  brands := []string{"Apple", "Samsung", "LG", "Philips"}
   sort.Strings(brands)
  fmt.Println(brands)                           // [Apple LG Philips Samsung]
  fmt.Println(sort.SearchStrings(brands, "LG")) // 1
}

反向排序​

keywords: sort.Reverse()​
func main() {
 numbers := []int{1, 5, 3, 6, 2}
 sort.Ints(numbers)
 fmt.Println(numbers) // [1 2 3 5 6]，ascending

 sort.Sort(sort.Reverse(sort.IntSlice(numbers)))
 fmt.Println(numbers) // [6 5 3 2 1]，descending
}

客製化欄位​

keywords: sort.Sort() sort.Interface​

只要有實作 sort.Interface 的 slice of structs 都可以使用 sort.Sort() 進行排序：

// https://tutorialedge.net/golang/go-sorting-with-sort-tutorial/
type Programmer struct {
 Name string
 Age  int
}

/* 建立一個符合 sort.interface 的  type */
type byAge []Programmer

func (p byAge) Len() int {
 return len(p)
}

func (p byAge) Swap(i, j int) {
 p[i], p[j] = p[j], p[i]
}

func (p byAge) Less(i, j int) bool {
 return p[i].Age < p[j].Age
}

func main() {
 programmers := []Programmer{
  {Name: "Aaron", Age: 30},
  {Name: "Bruce", Age: 20},
  {Name: "Candy", Age: 50},
  {Name: "Derek", Age: 1000},
 }

 sort.Sort(byAge(programmers))

 fmt.Println(programmers)
}

參考​