Merge pull request #133 from tao363/master

Update array stack

codes/cpp/chapter_stack_and_queue/array_stack.cpp

@@ -29,18 +29,22 @@ public:
 
     /* 出栈 */
     int pop() {
-        int oldTop = stack.back();
+        int oldTop = top();
         stack.pop_back();
         return oldTop;
     }
 
     /* 访问栈顶元素 */
     int top() {
+        if(empty())
+            throw out_of_range("栈为空");
         return stack.back();
     }
 
     /* 访问索引 index 处元素 */
     int get(int index) {
+        if(index >= size())
+            throw out_of_range("索引越界");
         return stack[index];
     }
 

codes/java/chapter_stack_and_queue/array_stack.java

@@ -33,16 +33,22 @@ class ArrayStack {
 
     /* 出栈 */
     public int pop() {
+        if (isEmpty())
+            throw new EmptyStackException();
         return stack.remove(size() - 1);
     }
 
     /* 访问栈顶元素 */
     public int peek() {
+        if (isEmpty())
+            throw new EmptyStackException();
         return stack.get(size() - 1);
     }
 
     /* 访问索引 index 处元素 */
     public int get(int index) {
+        if (index >= size())
+            throw new IndexOutOfBoundsException();
         return stack.get(index);
     }
 

codes/java/chapter_stack_and_queue/linkedlist_queue.java

@@ -57,7 +57,7 @@ class LinkedListQueue {
     /* 访问队首元素 */
     public int peek() {
         if (size() == 0)
-            throw new IndexOutOfBoundsException();
+            throw new EmptyStackException();
         return front.val;
     }
 

codes/java/chapter_stack_and_queue/linkedlist_stack.java

@@ -47,7 +47,7 @@ class LinkedListStack {
     /* 访问栈顶元素 */
     public int peek() {
         if (size() == 0)
-            throw new IndexOutOfBoundsException();
+            throw new EmptyStackException();
         return stackPeek.val;
     }
 

codes/javascript/chapter_stack_and_queue/array_stack.js

@@ -28,16 +28,19 @@ class ArrayStack {
 
     /* 出栈 */
     pop() {
+        if (this.empty()) throw "栈为空";
         return this.stack.pop();
     }
 
     /* 访问栈顶元素 */
     top() {
+        if (this.empty()) throw "栈为空";
         return this.stack[this.stack.length - 1];
     }
 
     /* 访问索引 index 处元素 */
     get(index) {
+        if (index >= this.size) throw "索引越界";
         return this.stack[index];
     }
 

codes/python/chapter_stack_and_queue/array_stack.py

@@ -27,14 +27,17 @@ class ArrayStack:
 
     """ 出栈 """
     def pop(self):
+        assert not self.is_empty(), "栈为空"
         return self.__stack.pop()
 
     """ 访问栈顶元素 """
     def peek(self):
+        assert not self.is_empty(), "栈为空"
         return self.__stack[-1]
 
     """ 访问索引 index 处元素 """
     def get(self, index):
+        assert index < self.size(), "索引越界"
         return self.__stack[index]
     
     """ 返回列表用于打印 """

codes/typescript/chapter_stack_and_queue/array_stack.ts

@@ -11,6 +11,7 @@ class ArrayStack {
     constructor() {
         this.stack = [];
     }
+
     /* 获取栈的长度 */
     get size(): number {
         return this.stack.length;
@@ -28,16 +29,19 @@ class ArrayStack {
 
     /* 出栈 */
     pop(): number | undefined {
+        if (this.empty()) throw new Error('栈为空');
         return this.stack.pop();
     }
 
     /* 访问栈顶元素 */
     top(): number | undefined {
+        if (this.empty()) throw new Error('栈为空');
         return this.stack[this.stack.length - 1];
     }
 
     /* 访问索引 index 处元素 */
     get(index: number): number | undefined {
+        if (index >= this.size) throw new Error('索引越界');
         return this.stack[index];
     }
 
@@ -83,4 +87,4 @@ console.log("栈的长度 size = " + size);
 const empty = stack.empty();
 console.log("栈是否为空 = " + empty);
 
-export { };
+export { };