说在前面

go version：go1.14.1 windows/amd64

实现

借助golang中的sort包可以方便的使用二分查找。

func Search(n int, f func(int) bool) int {
	// Define f(-1) == false and f(n) == true.
	// Invariant: f(i-1) == false, f(j) == true.
	i, j := 0, n
	for i < j {
		h := int(uint(i+j) >> 1) // avoid overflow when computing h
		// i ≤ h < j
		if !f(h) {
			i = h + 1 // preserves f(i-1) == false
		} else {
			j = h // preserves f(j) == true
		}
	}
	// i == j, f(i-1) == false, and f(j) (= f(i)) == true  =>  answer is i.
	return i
}

借助二分查找可以方便的实现有序列表。

代码

例如有序的uint64切片

func SeachUint64List(arr []uint64, x uint64) int {
	return sort.Search(len(arr), func(i int) bool {
		return arr[i] >= x
	})
}

func InsertOrderedUint64List(arr []uint64, x uint64) []uint64 {
	i := SeachUint64List(arr, x)

	arr = append(arr, 0)
	copy(arr[i+1:], arr[i:])
	arr[i] = x

	return arr
}

func main() {
	var arr []uint64

	arr = InsertOrderedUint64List(arr, 12)
	arr = InsertOrderedUint64List(arr, 2)
	arr = InsertOrderedUint64List(arr, 102)
	arr = InsertOrderedUint64List(arr, 1)
	arr = InsertOrderedUint64List(arr, 14542)
	arr = InsertOrderedUint64List(arr, 112)
	arr = InsertOrderedUint64List(arr, 142)

	fmt.Println(arr)
	// [1 2 12 102 112 142 14542]
}

其他的可以通过定义结构体，并使用Key进行排序，例如

type Node struct {
	Key   uint64
	Value string
}

func SeachNodeList(arr []*Node, x uint64) int {
	return sort.Search(len(arr), func(i int) bool {
		return arr[i].Key >= x
	})
}

func InsertOrderedNodeList(arr []*Node, x *Node) []*Node {
	if x == nil {
		return arr
	}

	i := SeachNodeList(arr, x.Key)

	arr = append(arr, &Node{})
	copy(arr[i+1:], arr[i:])
	arr[i] = x

	return arr
}

func main() {
	var arr []*Node

	arr = InsertOrderedNodeList(arr, &Node{Key: 12, Value: "ha"})
	arr = InsertOrderedNodeList(arr, &Node{Key: 1432, Value: "ta"})
	arr = InsertOrderedNodeList(arr, &Node{Key: 112, Value: "see"})
	arr = InsertOrderedNodeList(arr, &Node{Key: 1452, Value: "sight"})
	arr = InsertOrderedNodeList(arr, &Node{Key: 13332, Value: "peer"})
	arr = InsertOrderedNodeList(arr, &Node{Key: 12, Value: "one"})
	arr = InsertOrderedNodeList(arr, &Node{Key: 2, Value: "kiss"})

	for _, node := range arr {
		fmt.Println(*node)
	}
	
	// {2 kiss}
	// {12 one}
	// {12 ha}
	// {112 see}
	// {1432 ta}
	// {1452 sight}
	// {13332 peer}
}