北京小厂一面30问

**北京小厂一面30问**

作为一名技术面试官，我的目标是评估候选人的编程能力、问题解决能力以及对计算机科学的理解。以下是一些常见的问题，涵盖了编程语言、数据结构和算法等方面。

###1. 编程语言**Q1：你最熟悉的编程语言是什么？**

A：我最熟悉的是 Java 和 Python。Java 是一门面向对象的语言，广泛用于 Android 应用开发和企业级应用；Python 是一种高级语言，适合数据分析、机器学习和 web 开发。

**Q2：你能写出一个简单的 Hello World 程序吗？**

A：

javapublic class HelloWorld {
 public static void main(String[] args) {
 System.out.println("Hello, World!");
 }
}

javaimport java.util.EmptyStackException;

public class Stack {
 private Node top;
 private int size;

 public void push(int item) {
 Node node = new Node(item);
 if (top == null) {
 top = node;
 } else {
 node.prev = top;
 top.next = node;
 top = node;
 }
 size++;
 }

 public int pop() {
 if (isEmpty()) {
 throw new EmptyStackException();
 }
 Node node = top;
 top = top.prev;
 if (top != null) {
 top.next = null;
 } else {
 top = null;
 }
 size--;
 return node.item;
 }

 public boolean isEmpty() {
 return top == null;
 }

 private class Node {
 int item;
 Node prev;
 Node next;

 Node(int item) {
 this.item = item;
 }
 }
}

public class Queue {
 private Node front;
 private Node rear;
 private int size;

 public void enqueue(int item) {
 Node node = new Node(item);
 if (rear == null) {
 front = node;
 rear = node;
 } else {
 rear.next = node;
 node.prev = rear;
 rear = node;
 }
 size++;
 }

 public int dequeue() {
 if (isEmpty()) {
 throw new EmptyStackException();
 }
 Node node = front;
 front = front.next;
 if (front != null) {
 front.prev = null;
 } else {
 front = rear = null;
 }
 size--;
 return node.item;
 }

 public boolean isEmpty() {
 return front == null && rear == null;
 }

 private class Node {
 int item;
 Node prev;
 Node next;

 Node(int item) {
 this.item = item;
 }
 }
}

javapublic class QuickSort {
 public static void sort(int[] arr, int low, int high) {
 if (low < high) {
 int pivot = partition(arr, low, high);
 sort(arr, low, pivot -1);
 sort(arr, pivot +1, high);
 }
 }

 private static int partition(int[] arr, int low, int high) {
 int pivot = arr[high];
 int i = low -1;
 for (int j = low; j < high; j++) {
 if (arr[j] <= pivot) {
 i++;
 swap(arr, i, j);
 }
 }
 swap(arr, i +1, high);
 return i +1;
 }

 private static void swap(int[] arr, int i, int j) {
 int temp = arr[i];
 arr[i] = arr[j];
 arr[j] = temp;
 }
}

javapublic class Node {
 int data;
 Node next;

 public Node(int data) {
 this.data = data;
 this.next = null;
 }
}

public class LinkedList {
 private Node head;

 public void addNode(int data) {
 Node node = new Node(data);
 if (head == null) {
 head = node;
 } else {
 Node temp = head;
 while (temp.next != null) {
 temp = temp.next;
 }
 temp.next = node;
 }
 }

 public void printList() {
 Node temp = head;
 while (temp != null) {
 System.out.print(temp.data + " ");
 temp = temp.next;
 }
 System.out.println();
 }
}