mirror of
https://github.com/duke-git/lancet.git
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119 lines
2.3 KiB
Go
119 lines
2.3 KiB
Go
package datastructure
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import (
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"errors"
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"fmt"
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"reflect"
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)
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// CircularQueue implements circular queue with slice,
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// last index of CircularQueue don't contain value, so acturl capacity is size - 1
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type CircularQueue[T any] struct {
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data []T
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front int
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rear int
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size int
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}
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// NewCircularQueue return a empty CircularQueue pointer
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func NewCircularQueue[T any](size int) *CircularQueue[T] {
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data := make([]T, size)
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return &CircularQueue[T]{data: data, front: 0, rear: 0, size: size}
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}
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// Data return slice of queue data
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func (q *CircularQueue[T]) Data() []T {
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data := []T{}
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front := q.front
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rear := q.rear
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if front <= rear {
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return q.data[front:rear]
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}
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data = append(data, q.data[front:]...)
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data = append(data, q.data[0:rear]...)
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return data
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}
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// Length return current data length of queue
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func (q *CircularQueue[T]) Length() int {
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if q.size == 0 {
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return 0
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}
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return (q.rear - q.front + q.size) % q.size
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}
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// IsEmpty checks if queue is empty or not
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func (q *CircularQueue[T]) IsEmpty() bool {
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return q.front == q.rear
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}
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// IsFull checks if queue is full or not
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func (q *CircularQueue[T]) IsFull() bool {
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return (q.rear+1)%q.size == q.front
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}
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// Front return front value of queue
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func (q *CircularQueue[T]) Front() T {
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return q.data[q.front]
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}
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// Back return back value of queue
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func (q *CircularQueue[T]) Back() T {
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if q.rear-1 >= 0 {
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return q.data[q.rear-1]
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}
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return q.data[q.size-1]
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}
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// Enqueue put element into queue
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func (q *CircularQueue[T]) Enqueue(value T) error {
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if q.IsFull() {
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return errors.New("queue is full!")
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}
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q.data[q.rear] = value
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q.rear = (q.rear + 1) % q.size
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return nil
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}
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// Dequeue remove head element of queue and return it, if queue is empty, return nil and error
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func (q *CircularQueue[T]) Dequeue() (*T, error) {
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if q.IsEmpty() {
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return nil, errors.New("queue is empty")
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}
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headItem := q.data[q.front]
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var t T
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q.data[q.front] = t
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q.front = (q.front + 1) % q.size
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return &headItem, nil
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}
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// Clear the queue data
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func (q *CircularQueue[T]) Clear() {
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q.data = []T{}
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q.front = 0
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q.rear = 0
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q.size = 0
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}
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// Contain checks if the value is in queue or not
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func (q *CircularQueue[T]) Contain(value T) bool {
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for _, v := range q.data {
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if reflect.DeepEqual(v, value) {
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return true
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}
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}
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return false
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}
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// Print queue data
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func (q *CircularQueue[T]) Print() {
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fmt.Printf("%+v\n", q)
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}
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