82 lines
1.4 KiB
Go
82 lines
1.4 KiB
Go
package dsUtils
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import (
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"io"
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"sync"
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)
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type IStack[T any] interface {
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Push(item T)
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Get() T
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Len() int
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}
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// Stack isn't thread safe and suppose to be used only in a single thread
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// For multithreaded usage -- use Stack
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type Stack[T any] struct {
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IStack[T]
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Buffer []T
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}
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// NewStack creates a new Stack instance
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func NewStack[T any]() *Stack[T] {
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return &Stack[T]{}
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}
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func (s *Stack[T]) Push(item T) {
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s.Buffer = append(s.Buffer, item)
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}
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func (s *Stack[T]) Get() (T, error) {
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if len(s.Buffer) == 0 {
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var out T
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return out, io.EOF
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}
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item := s.Buffer[len(s.Buffer)-1]
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s.Buffer = s.Buffer[:len(s.Buffer)-1]
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return item, nil
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}
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func (s *Stack[T]) Len() int {
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return len(s.Buffer)
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}
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// StackSync is a Stack but for multi thread usage
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type StackSync[T any] struct {
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IStack[T]
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Buffer []T
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Mu *sync.Mutex
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NonEmptyCond *sync.Cond
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}
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func NewStackSync[T any]() *StackSync[T] {
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return &StackSync[T]{
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Mu: &sync.Mutex{},
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NonEmptyCond: sync.NewCond(&sync.RWMutex{}),
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}
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}
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func (s *StackSync[T]) Push(item T) {
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s.Mu.Lock()
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s.Buffer = append(s.Buffer, item)
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s.NonEmptyCond.Signal()
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s.Mu.Unlock()
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}
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func (s *StackSync[T]) Get() T {
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s.Mu.Lock()
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if len(s.Buffer) < 1 {
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s.NonEmptyCond.Wait()
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}
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item := s.Buffer[len(s.Buffer)-1]
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s.Buffer = s.Buffer[:len(s.Buffer)-1]
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s.Mu.Unlock()
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return item
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}
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func (s *StackSync[T]) Len() int {
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s.Mu.Lock()
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defer s.Mu.Lock()
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return len(s.Buffer)
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}
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