fine tune

codes/javascript/chapter_stack_and_queue/linkedlist_stack.js

@@ -36,9 +36,6 @@ class LinkedListStack {
     /* 出栈 */
     pop() {
         const num = this.peek();
-        if (!this.#stackPeek) {
-            throw new Error("栈为空！");
-        }
         this.#stackPeek = this.#stackPeek.next;
         this.#stkSize--;
         return num;
@@ -46,9 +43,8 @@ class LinkedListStack {
 
     /* 访问栈顶元素 */
     peek() {
-        if (!this.#stackPeek) {
+        if (!this.#stackPeek)
             throw new Error("栈为空！");
-        }
         return this.#stackPeek.val;
     }
 

codes/typescript/chapter_stack_and_queue/linkedlist_stack.ts

@@ -36,9 +36,8 @@ class LinkedListStack {
     /* 出栈 */
     pop(): number {
         const num = this.peek();
-        if (!this.stackPeek) {
-            throw new Error("栈为空！");
-        }
+        if (!this.stackPeek)
+            throw new Error("栈为空");
         this.stackPeek = this.stackPeek.next;
         this.stkSize--;
         return num;
@@ -46,9 +45,8 @@ class LinkedListStack {
 
     /* 访问栈顶元素 */
     peek(): number {
-        if (!this.stackPeek) {
-            throw new Error("栈为空！");
-        }
+        if (!this.stackPeek)
+            throw new Error("栈为空");
         return this.stackPeek.val;
     }