Dart 栈，队列，循环队列

Author: tianqing.liang

03Insertion-Sort/InsertionSort.dart

@@ -11,9 +11,8 @@ void main() {
   var list2 = ["2","4","6","3","1","5"];
   var list3 = [2, 4, 6, 3, 1, 5];
   sort(list);
-  insertionSort(list);
+  insertionSort(list2);
   insertionSort2(list3);
-
 }
 
 //Dart语言原生方法
@@ -91,7 +90,6 @@ void swap(arr, int i, int j) {
 //   * of the given list [:a:].
 //   *
 //   * If the given range is invalid an "OutOfRange" error is raised.
-//   * TODO(floitsch): do we want an error?
 //   *
 //   * See [:sort:] for requirements of the [:compare:] function.
 //   */

04Stack-Queue/ArrayQueue.dart

@@ -0,0 +1,47 @@
+import 'Queue.dart';
+class ArrayQueue implements Queue{
+
+  List? arr;
+  ArrayQueue(){
+    arr =<dynamic>[];
+  }
+
+  @override
+  dequeue() {
+    arr!.removeAt(0);
+  }
+
+  @override
+  void enqueue(e) {
+    arr!.add(e);
+  }
+
+  @override
+  getFront() {
+    return arr![0];
+  }
+
+  @override
+  int getSize() {
+    return arr!.length;
+  }
+
+  @override
+  bool isEmpty() {
+    return arr!.isEmpty;
+  }
+
+  @override
+  String toString() {
+    StringBuffer buffer = new StringBuffer();
+    buffer.write("Queue: ");
+    buffer.write('front [');
+    for(int i = 0 ; i < arr!.length ; i ++){
+      buffer.write(arr![i]);
+      if(i != arr!.length - 1)
+        buffer.write(", ");
+    }
+    buffer.write("] tail");
+    return buffer.toString();
+  }
+}

04Stack-Queue/ArrayStack.dart

@@ -0,0 +1,46 @@
+import 'Stack.dart';
+class ArrayStack<T> implements Stack<T>{
+
+  List? arr;
+  ArrayStack(){
+    arr =<dynamic>[];
+  }
+
+  @override
+  int getSize() {
+    return arr!.length;
+  }
+
+  @override
+  bool isEmpty() {
+    return arr!.isEmpty;
+  }
+
+  @override
+  T peek() {
+    return arr![0];
+  }
+
+  @override
+  T pop() => arr!.removeLast();
+
+  @override
+  void push(T e) {
+    arr!.add(e);
+  }
+
+  @override
+  String toString() {
+    StringBuffer buffer = new StringBuffer();
+    buffer.write("Stack: ");
+    buffer.write('[');
+    for(int i = 0 ; i < arr!.length ; i ++){
+      buffer.write(arr![i]);
+      if(i != arr!.length - 1)
+        buffer.write(", ");
+    }
+    buffer.write("] top");
+    return buffer.toString();
+  }
+
+}

04Stack-Queue/LoopQueue.dart

@@ -0,0 +1,83 @@
+import 'Queue.dart';
+
+class LoopQueue<T> implements Queue<T>{
+
+  List? arr;
+  int front = 0,tail=0;
+  int size =0;
+
+  LoopQueue(){
+    arr = List.filled(10, false);
+  }
+
+  int getCapacity(){
+    int capacity =  arr!.length;
+    return capacity;
+  }
+
+  @override
+  dequeue() {
+    T ret = arr![front];
+    arr![front] = null;
+    front = (front + 1) % arr!.length;
+    size--;
+    if(size == getCapacity() / 4 && getCapacity() / 2 != 0){
+      resize((getCapacity()/2) as int);
+    }
+    return ret;
+  }
+
+  void resize(int newCapacity){
+
+    List? newArr = List.filled(newCapacity, false);
+    for(int i = 0 ; i < arr!.length ; i ++){
+      newArr[i] = arr![(i + front) % arr!.length];
+    }
+    arr = newArr;
+    front = 0;
+    tail = size;
+  }
+
+  @override
+  void enqueue(e) {
+
+    if((tail + 1) % arr!.length == front)
+      resize(getCapacity() * 2);
+    arr![tail] = e;
+    tail = (tail + 1) % arr!.length;
+    size++;
+  }
+
+  @override
+  getFront() {
+    if(isEmpty()){
+      throw Exception("Queue is empty.");
+    }
+    return arr![front];
+  }
+
+  @override
+  int getSize() {
+    return arr!.length;
+  }
+
+  @override
+  bool isEmpty() {
+    return front == tail ;
+  }
+
+  @override
+  String toString() {
+    StringBuffer buffer = new StringBuffer();
+    buffer.write("Queue: size = $size , capacity = ${getCapacity()} \n");
+    buffer.write('front [');
+    for(int i = front ; i != tail ; i = (i + 1) % arr!.length){
+      buffer.write(arr![i]);
+      if((i + 1) % arr!.length != tail)
+        buffer.write(", ");
+    }
+    buffer.write("] tail");
+    return buffer.toString();
+  }
+
+}

04Stack-Queue/Main.dart

@@ -0,0 +1,34 @@
+import 'ArrayStack.dart';
+import 'ArrayQueue.dart';
+import 'LoopQueue.dart';
+
+void main(){
+//  ArrayStack<int> stack = new ArrayStack<int>();
+//  for(int i = 0 ; i < 10 ; i ++){
+//    stack.push(i);
+//    print(stack.toString());
+//  }
+//  stack.pop();
+//
+  ArrayQueue queue = new ArrayQueue();
+  for(int i = 0 ; i < 20 ; i ++){
+    queue.enqueue(i);
+    print(queue);
+    if(i % 3 == 2){
+      print('----出栈头部元素-----');
+      queue.dequeue();
+      print(queue);
+    }
+  }
+
+  LoopQueue<int> loopQueue = new LoopQueue<int>();
+  for(int i = 0 ; i < 30 ; i ++){
+    loopQueue.enqueue(i);
+    print(loopQueue);
+
+    if(i % 3 == 2){
+      loopQueue.dequeue();
+      print(loopQueue);
+    }
+  }
+}

04Stack-Queue/Queue.dart

@@ -0,0 +1,7 @@
+abstract class Queue<T>{
+  int getSize();
+  bool isEmpty();
+  void enqueue(T e);
+  T dequeue();
+  T getFront();
+}

04Stack-Queue/Stack.dart

@@ -0,0 +1,7 @@
+abstract class Stack<T>{
+  int getSize();
+  bool isEmpty();
+  void push(T e);
+  T pop();
+  T peek();
+}

README.md

@@ -5,4 +5,6 @@
 1. 线性搜索
 2. 选择排序
 3. 插入排序
+4. 栈，队列，循环队列
+