解释这段代码:Server.text.offer(str + "|" + "欢迎" + name + "进入聊天室");
时间: 2023-07-08 14:25:17 浏览: 45
这段代码是指在一个聊天室的服务器端,当有新用户进入聊天室时,向所有已连接的用户发送欢迎消息。具体来说,代码中的 `Server.text` 可能是一个消息队列,`offer()` 则是向队列中添加一条新的消息。`str + "|" + "欢迎" + name + "进入聊天室"` 则是一条字符串消息,其中 `str` 可能是一些标识信息,比如用户名或者用户 IP 地址等等。整条消息的意思是:用户 `name` 进入聊天室,欢迎他/她的到来。
相关问题
剑指offer+java
《剑指Offer》是一本非常经典的面试题集,主要涵盖了程序员面试中常见的算法和数据结构问题。以下是一些Java实现的剑指Offer题目:
1. 面试题3:数组中重复的数字
```java
public boolean duplicate(int[] nums, int length, int[] duplication) {
if (nums == null || length <= 0) {
return false;
}
for (int i = 0; i < length; i++) {
while (nums[i] != i) {
if (nums[i] == nums[nums[i]]) {
duplication[0] = nums[i];
return true;
}
swap(nums, i, nums[i]);
}
}
return false;
}
private void swap(int[] nums, int i, int j) {
int temp = nums[i];
nums[i] = nums[j];
nums[j] = temp;
}
```
2. 面试题10:斐波那契数列
```java
public int Fibonacci(int n) {
if (n <= 1) {
return n;
}
int pre2 = 0, pre1 = 1;
int fib = 0;
for (int i = 2; i <= n; i++) {
fib = pre2 + pre1;
pre2 = pre1;
pre1 = fib;
}
return fib;
}
```
3. 面试题14:剪绳子
```java
public int maxProductAfterCutting(int length) {
if (length < 2) {
return 0;
}
if (length == 2) {
return 1;
}
if (length == 3) {
return 2;
}
int[] products = new int[length + 1];
products[0] = 0;
products[1] = 1;
products[2] = 2;
products[3] = 3;
int max = 0;
for (int i = 4; i <= length; i++) {
max = 0;
for (int j = 1; j <= i / 2; j++) {
int product = products[j] * products[i - j];
if (max < product) {
max = product;
}
products[i] = max;
}
}
max = products[length];
return max;
}
```
class BiTreeNode: def __init__(self, data=None): self.data = data self.l_child = None self.r_child = None class BiTree(object): def __init__(self, root=None): self.r_child = None self.l_child = None self.root = root @classmethod def createBiTree(cls, order): q = LinkQueue() root = BiTreeNode() print("节点个数") bt.nodeCount(bt.root) print() bt = BiTree(root) q.offer(root) for i in range(len(order)): c = order[i] node = q.peek() if node.l_child is None: newNode = BiTreeNode(c) node.l_child = newNode q.offer(newNode) elif node.r_child is None: newNode = BiTreeNode(c) node.r_child = newNode q.offer(newNode) q.poll() return bt def Order(self, root): q = LinkQueue() q.offer(root) while not q.isEmpty(): p = q.poll() print(p.data, end='') if p.l_child is not None: q.offer(p.l_child) if p.r_child is not None: q.offer(p.r_child) def nodeCount(t): count = 0 if t is not None: count += 1 count += nodeCount(t.l_child) count += nodeCount(t.r_child) return count
代码中存在两个问题:
1. 在createBiTree方法中,先调用了bt.nodeCount方法,再将root节点传入BiTree类的构造方法中,这会导致nodeCount方法中的t参数为None,从而导致程序抛出异常。
2. nodeCount方法应该是BiTree类的方法,而不是独立的函数。因此,应该将nodeCount方法移动到BiTree类中,并将其改为实例方法。
修改后的代码如下:
```
from queue import Queue
class BiTreeNode:
def __init__(self, data=None):
self.data = data
self.l_child = None
self.r_child = None
class BiTree(object):
def __init__(self, root=None):
self.root = root
@classmethod
def createBiTree(cls, order):
q = Queue()
root = BiTreeNode()
bt = BiTree(root)
q.put(root)
for i in range(len(order)):
c = order[i]
node = q.get()
if node.l_child is None:
newNode = BiTreeNode(c)
node.l_child = newNode
q.put(newNode)
elif node.r_child is None:
newNode = BiTreeNode(c)
node.r_child = newNode
q.put(newNode)
return bt
def Order(self, root):
q = Queue()
q.put(root)
while not q.empty():
p = q.get()
print(p.data, end='')
if p.l_child is not None:
q.put(p.l_child)
if p.r_child is not None:
q.put(p.r_child)
def nodeCount(self, t):
count = 0
if t is not None:
count += 1
count += self.nodeCount(t.l_child)
count += self.nodeCount(t.r_child)
return count
```
修改后的代码中,将nodeCount方法移动到BiTree类中,并将其改为实例方法。同时,将createBiTree方法中的节点计数移动到Order方法中,确保root节点已经被正确初始化。另外,将LinkQueue替换为Python内置的Queue。