BitMap

BitMap的golang实现

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package main

import "fmt"

type BitMap []uint64

func NewBitMap(nBits int) *BitMap {
	bytesLength := ((nBits - 1) / 64 ) + 1
	tmp := BitMap(make([]uint64, bytesLength, bytesLength))
	return &tmp
}

func (this *BitMap) Set(k int) {
	bytess := k / 64
	bits := uint64(k % 64)
	(*this)[bytess] |= uint64(0x01) << bits
}

func (this *BitMap) unset(k int) {
	bytess := k / 64
	bits := uint64(k % 64)
	(*this)[bytess] |= ^(uint64(0x01) << bits)
}

func (this *BitMap) get(k int) bool {
	bytess := k / 64
	bits := uint64(k % 64)
	return (*this)[bytess] & ( uint64(0x01) << bits) !=0
}

func main()  {
	bit:= NewBitMap(100)
	bit.Set(10)
	fmt.Println(bit.get(10))
	fmt.Println(bit.get(11))
	fmt.Println(bit.get(9))
	bit.unset(10)
	fmt.Println(bit.get(10))

}