feat: add typescript solution to locf problem: No.09. Implement Queue using Stacks (doocs#428)

Author: zhaocchen

lcof/面试题09. 用两个栈实现队列/README.md

@@ -206,6 +206,46 @@ public:
 };
 ```
 
+### **TypeScript**
+
+```ts
+class CQueue {
+    private stack1: number[];
+    private stack2: number[];
+    constructor() {
+        this.stack1 = [];
+        this.stack2 = [];
+    }
+
+    appendTail(value: number): void {
+        this.stack1.push(value);
+        if (this.stack2.length == 0) {
+            this.move();
+        }
+    }
+
+    move(): void {
+        while (this.stack1.length != 0) {
+            this.stack2.push(this.stack1.pop());
+        }
+    }
+
+    deleteHead(): number {
+        if (this.stack2.length == 0) {
+            this.move();
+        }
+        return this.stack2.length == 0 ? -1 : this.stack2.pop();
+    }
+}
+
+/**
+ * Your CQueue object will be instantiated and called as such:
+ * var obj = new CQueue()
+ * obj.appendTail(value)
+ * var param_2 = obj.deleteHead()
+ */
+```
+
 ### **...**
 
 ```

lcof/面试题09. 用两个栈实现队列/Solution.ts

@@ -0,0 +1,35 @@
+class CQueue {
+    private stack1: number[];
+    private stack2: number[];
+    constructor() {
+        this.stack1 = [];
+        this.stack2 = [];
+    }
+
+    appendTail(value: number): void {
+        this.stack1.push(value);
+        if (this.stack2.length == 0) {
+            this.move();
+        }
+    }
+
+    move(): void {
+        while (this.stack1.length != 0) {
+            this.stack2.push(this.stack1.pop());
+        }
+    }
+
+    deleteHead(): number {
+        if (this.stack2.length == 0) {
+            this.move();
+        }
+        return this.stack2.length == 0 ? -1 : this.stack2.pop();
+    }
+}
+
+/**
+ * Your CQueue object will be instantiated and called as such:
+ * var obj = new CQueue()
+ * obj.appendTail(value)
+ * var param_2 = obj.deleteHead()
+ */