github.com/yindaheng98/go-utility/SortedSet

Introduction

Sorted set is a special type set in which all the element can be sorted. This package implement a sorted set based on map in go and the package Skiplist.

Usage

This package has a interface Element and a struct SortedSet

Implement a interface

The interface Element defines the element that can be stored in SortedSet. This interface is very simple:

type Element interface {
	GetName() string
}

The method GetName() defined the unique name of an element. If two elements' GetName() returns the same string, they will be regarded as the same element.

Create a SortedSet

Just call the function New(...) and input a initial size, you can get a sorted set:

set := New(100)

The initial size "100" does not mean that this set can not store No.101 elements. It only determines the index level of the skip list inside the sorted set.

Add and change an element

The sorted set use a float number for sorting, called "weight". You can add an element with weight 1.2 like this:

set.Update(element, 1.2)

Or you can increase the weight of an element by 0.2:

set.UpdateDelta(element, 0.2)

Or even increase all the weight in the sorted set:

set.DeltaUpdateAll(0.2)

Get the weight of an element

weight, ok := set.GetWeight(element)

if the element exists, the weight will be returned and ok will be true. If not, ok will be false.

Output sorted element

This methods returns a list of the element, with the ascending order of their weight:

func (set *SortedSet) SortedAll() []Element

Or if you do not want all the elements, you can get the smallest n(uint64) elements in the list:

func (set *SortedSet) Sorted(n uint64) []Element

How much elements?

This method returns how much element are in the sorted set.

func (set *SortedSet) Count() uint64