githaven/vendor/github.com/couchbase/vellum/regexp/sparse.go
2018-05-19 20:49:46 +08:00

55 lines
1.2 KiB
Go

// Copyright (c) 2017 Couchbase, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package regexp
type sparseSet struct {
dense []uint
sparse []uint
size uint
}
func newSparseSet(size uint) *sparseSet {
return &sparseSet{
dense: make([]uint, size),
sparse: make([]uint, size),
size: 0,
}
}
func (s *sparseSet) Len() int {
return int(s.size)
}
func (s *sparseSet) Add(ip uint) uint {
i := s.size
s.dense[i] = ip
s.sparse[ip] = i
s.size++
return i
}
func (s *sparseSet) Get(i uint) uint {
return s.dense[i]
}
func (s *sparseSet) Contains(ip uint) bool {
i := s.sparse[ip]
return i < s.size && s.dense[i] == ip
}
func (s *sparseSet) Clear() {
s.size = 0
}