合集-手撕算法
摘要：数组，字符串 最后一个单词长度 class Solution: def lengthOfLastWord(self, s: str) -> int: end = len(s) - 1 while s[end] == " ": end -= 1 start = end while start >= 0
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摘要：有效的电话号码 grep -E '^(\([0-9]{3}\) [0-9]{3}-[0-9]{4}|[0-9]{3}-[0-9]{3}-[0-9]{4})$' file.txt 打印第十行 awk "NR==10" file.txt sed -n '10p' file.txt tail -n +10
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摘要：删除重复的电子邮箱 delete from Person where id not in (select id from (select min(id) as id from Person group by email) as temp) 好友申请 II ：谁有最多的好友 select id,cou
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摘要：懒汉式 public class Singleton { private static Singleton instance; private Singleton (){} public static Singleton getInstance() { if (instance == null) {
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摘要：多线程循环打印ABC import java.util.concurrent.locks.Condition; import java.util.concurrent.locks.ReentrantLock; public class Main { public static ReentrantLo
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摘要：两个线程交替打印0-100 import java.util.concurrent.locks.Condition; import java.util.concurrent.locks.ReentrantLock; public class Main { public static Reentran
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摘要：首先来看线程不安全的转账 public class Bank { private int[] accounts; public Bank() { this.accounts = new int[10]; for (int i = 0; i < 10; i++) { accounts[i] = 100
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摘要：一种不安全的写法 public class Main { public static final Object lock1 = new Object(); public static final Object lock2 = new Object(); public static void main
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摘要：import java.util.LinkedList; import java.util.Queue; import java.util.concurrent.locks.Condition; import java.util.concurrent.locks.ReentrantLock; pub
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摘要：public class Main { public static void main(String[] args) throws InterruptedException, FileNotFoundException { try(FileInputStream file = new FileInp
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摘要：import java.io.*; import java.sql.Time; import java.util.*; import java.util.concurrent.*; import java.util.concurrent.atomic.AtomicInteger; import ja
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摘要：# Definition for singly-linked list. # class ListNode: # def __init__(self, val=0, next=None): # self.val = val # self.next = next class Solution: def
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摘要：# Definition for singly-linked list. # class ListNode: # def __init__(self, val=0, next=None): # self.val = val # self.next = next class Solution: def
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摘要：# Definition for singly-linked list. # class ListNode: # def __init__(self, val=0, next=None): # self.val = val # self.next = next class Solution: def
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摘要：# Definition for singly-linked list. # class ListNode: # def __init__(self, val=0, next=None): # self.val = val # self.next = next class Solution: def
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摘要：# Definition for singly-linked list. # class ListNode: # def __init__(self, x): # self.val = x # self.next = None class Solution: def removeDuplicateN
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摘要：检测环 快慢指针法是一种用于检测链表中是否存在环的有效方法，同时也可以找到环的起点。该方法的原理基于两个指针在链表上同时移动，其中一个移动得更快，而另一个移动得更慢。 检测环的存在： 使用两个指针，一个称为快指针（fast），一个称为慢指针（slow）。 在每一步中，快指针向前移动两步，而慢指针只移
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摘要：# Definition for singly-linked list. # class ListNode: # def __init__(self, val=0, next=None): # self.val = val # self.next = next class Solution: def
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摘要：class Node: def __init__(self, key=0, val=0, pre=None, next=None, fre=0, tail=None): self.key = key self.val = val self.pre = pre self.next = next sel
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摘要：class Node: def __init__(self, key=0, value=0): self.key = key self.value = value self.prev = None self.next = None class LRUCache: def __init__(self,
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