78 lines
1.9 KiB
Go
78 lines
1.9 KiB
Go
/*
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* Amsterdam Web Communities System
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* Copyright (c) 2025 Erbosoft Metaverse Design Solutions, All Rights Reserved
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*
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* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at https://mozilla.org/MPL/2.0/.
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*
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* SPDX-License-Identifier: MPL-2.0
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*/
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// Package util contains utility definitions.
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package util
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// Stack[T] is a simple generic array-based stack implementation.
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type Stack[T comparable] struct {
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elements []T
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}
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// IsEmpty returns true if the stack is empty.
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func (stk *Stack[T]) IsEmpty() bool {
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return len(stk.elements) == 0
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}
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// Push adds a value to the top of the stack.
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func (stk *Stack[T]) Push(data T) {
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stk.elements = append(stk.elements, data)
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}
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// Pop removes and returns a value from the top of the stack.
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func (stk *Stack[T]) Pop() (T, bool) {
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if stk.IsEmpty() {
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return *new(T), false
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}
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topElement := stk.elements[len(stk.elements)-1]
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stk.elements = stk.elements[:len(stk.elements)-1]
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return topElement, true
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}
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// Peek returns the current value on the top of the stack.
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func (stk *Stack[T]) Peek() (T, bool) {
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if stk.IsEmpty() {
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return *new(T), false
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}
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return stk.elements[len(stk.elements)-1], true
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}
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// RemoveMostRecent looks for the most recent particular data element on the stack, and removes that.
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func (stk *Stack[T]) RemoveMostRecent(data T) bool {
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i := len(stk.elements) - 1
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for i >= 0 {
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if stk.elements[i] == data {
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if i == 0 {
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stk.elements = stk.elements[1:]
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} else if (i + 1) == len(stk.elements) {
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stk.elements = stk.elements[:i]
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} else {
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stk.elements = append(stk.elements[:i], stk.elements[i+1:]...)
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}
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return true
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}
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i--
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}
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return false
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}
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// Clear clears out the stack.
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func (stk *Stack[T]) Clear() {
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stk.elements = make([]T, 0)
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}
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// NewStack creates and returns a new stack.
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func NewStack[T comparable]() *Stack[T] {
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return &Stack[T]{
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elements: make([]T, 0),
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}
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}
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