标准模板库的一些函数

不念不忘少年蓝@ 2022-06-11 09:21 128阅读 0赞

#ifndef _ITERATOR_DEBUG_LEVEL
    #define _ITERATOR_DEBUG_LEVEL 0
    #else
    #undef _ITERATOR_DEBUG_LEVEL
    #define _ITERATOR_DEBUG_LEVEL 0
    #endif
    
    #include <iostream>
    #include <string>
    #include <algorithm> //算法
    
    using namespace std;
    
    //STL standard template libary 标准模(mu)板库 C++一部分，编译器自带
    //Android NDK支持
    //java.lang java.util包中API，java的一部分
    
    //string初始化
    
    void main()
    {
    	//string由c字符串衍生过来的
    	string s1 = "craig david";
    	string s2("7 days");
    	string s3 = s2;
    	string s4(10,'a');
    
    	cout << s4 << endl;
    
    	system("pause");
    }
    
    //string遍历
    void main()
    {
    	string s1 = "craig david";
    	//			 ^
    	//1 数组方式
    	for (int i = 0; i < s1.length(); i++)
    	{
    		cout << s1[i] << endl;
    	}
    	//2 迭代器指针
    	for (string::iterator it = s1.begin(); it != s1.end(); it++)
    	{
    		cout << *it << " ";
    	}
    	cout << endl;
    	//3 at函数(charAt)
    	// 可能会抛出异常
    	try
    	{
    		for (int i = 0; i < s1.length() + 3; i++)
    		{
    			cout << s1.at(i) << " ";
    		}
    	}
    	catch (...)
    	{
    		cout << "异常" << endl;
    	}
    
    
    	system("pause");
    }
    
    
    //string字符串->c字符串转换
    void main()
    {
    	//string -> char*
    	string s1 = "walking away";
    	const char* c = s1.c_str();
    	printf("%s\n",c);
    
    	//
    	string s2 = c;
    
    	//string->char[]
    	//从string中赋值字符到char[]
    	char arr[50] = {0};
    	s1.copy(arr,4,0);
    	
    	cout << arr << endl;
    
    	system("pause");
    }
    
    
    //字符串拼接
    void main()
    {
    	string s1 = "alan";
    	string s2 = "jackson";
    	
    	//1.
    	string s3 = s1 + s2;
    
    	string s4 = " pray";
    
    	//2.
    	s3.append(s4);
    
    	cout << s3 << endl;
    
    	system("pause");
    }
    
    //字符串查找替换
    void main()
    {
    	string s1 = "apple google apple iphone";
    	//从0开始查找"google"的位置
    	int idx = s1.find("google", 0);
    	cout << idx << endl;
    
    	//统计apple出现的次数
    	int idx_app = s1.find("apple",0);
    	//npos大于任何有效下标的值
    	int num = 0;
    	while (idx_app != string::npos)
    	{
    		num++;
    		cout << "找到的索引:" << idx_app << endl;
    		idx_app+=5;
    		idx_app = s1.find("apple", idx_app);
    	}
    
    	cout << num << endl;
    	system("pause");
    }
    
    void main()
    {
    	string s1 = "apple google apple iphone";
    	//0-5（不包含5）替换为jobs
    	s1.replace(0, 5, "jobs");
    	cout << s1 << endl;
    
    	//所有apple替换为jobs
    	int idx = s1.find("apple", 0);
    	while (idx != string::npos)
    	{
    		s1.replace(idx, 5, "jobs");
    		idx += 5;
    		idx = s1.find("apple", idx);
    	}
    
    	cout << s1 << endl;
    	system("pause");
    }
    
    //删除（截取）和插入
    void main()
    {
    	string s1 = "apple google apple iphone";
    	//删除a，找到a所在的指针
    	string::iterator it = find(s1.begin(),s1.end(),'g');
    	//只能删除一个字符
    	s1.erase(it);
    	
    	//开头末尾插入字符串
    	s1.insert(0, "macos");
    	s1.insert(s1.length(), " facebook");
    
    	cout << s1 << endl;
    	system("pause");
    }
    
    //java StringBuffer才可变
    //String 不可变
    //大小写转换
    void main()
    {
    	string s1 = "JASON";
    	//原始字符串的起始地址，原始字符串的结束地址, 目标字符串的起始地址, 函数名称
    	transform(s1.begin(), s1.end()-1,s1.begin(), tolower);
    	cout << s1 << endl;
    
    
    	transform(s1.begin(), s1.end() - 1, s1.begin(), toupper);
    	cout << s1 << endl;
    
    	system("pause");
    }
    
    
    //容器
    //Vector
    //初始化
    #include <vector>
    void printVector(vector<int> &v)
    {
    	//通过数组的方式遍历
    	for (int i = 0; i < v.size(); i++)
    	{
    		cout << v[i] << endl;
    	}
    }
    void main()
    {
    	//1.
    	vector<int> v1;
    	v1.push_back(20);
    	v1.push_back(40);
    	v1.push_back(15);
    	v1.push_back(7);
    
    	//2.
    	vector<int> v2 = v1;
    
    	//3.部分复制
    	vector<int> v3(v1.begin(),v1.begin()+2);
    	
    	printVector(v3);
    	
    
    	system("pause");
    }
    
    //添加 删除
    void main()
    {
    	//添加到结尾
    	vector<int> v1;
    	v1.push_back(20);
    	v1.push_back(40);
    	v1.push_back(15);
    	v1.push_back(7);
    
    	//访问头部
    	v1.front() = 11;
    	//访问尾部
    	v1.back() = 90;
    
    	//删除结尾的元素
    	//v1.pop_back();
    	while (v1.size() > 0)
    	{
    		cout << "末尾的元素：" << v1.back() << endl;
    		v1.pop_back();
    	}
    
    	printVector(v1);
    
    	system("pause");
    }
    
    //数组的方式
    void main()
    {
    	vector<int> v1;
    	v1.push_back(20);
    	v1.push_back(40);
    	v1.push_back(15);
    	v1.push_back(7);
    
    	v1[2] = v1[2] +10;
    
    	//容器等价于动态数组	
    	vector<int> v2(10);
    	for (int i = 0; i < v2.size(); i++)
    	{
    		v2[i] = i + 1;
    	}
    
    	printVector(v2);
    
    	system("pause");
    }
    
    //迭代器遍历
    //迭代器的种类（正向，反向迭代器）
    void main()
    {
    	vector<int> v1;
    	v1.push_back(20);
    	v1.push_back(40);
    	v1.push_back(15);
    	v1.push_back(7);
    	//正向
    	for (vector<int>::iterator it = v1.begin(); it < v1.end(); it++)
    	{
    		cout << *it << endl;
    	}
    	cout << "-----------------" << endl;
    	//反向迭代
    	for (vector<int>::reverse_iterator it = v1.rbegin(); it < v1.rend(); it++)
    	{
    		cout << *it << endl;
    	}
    
    	system("pause");
    }
    
    //删除
    void main()
    {
    	vector<int> v1(10);
    	for (int i = 0; i < v1.size(); i++)
    	{
    		v1[i] = i + 1;
    	}
    
    	//删除指定位置
    	vector<int>::iterator it = v1.begin();
    	it += 3;
    	v1.erase(it);
    
    	//distance(v1.begin(), it);
    
    	//删除区间
    	v1.erase(v1.begin(), v1.begin() + 3);
    
    	for (vector<int>::iterator it = v1.begin(); it < v1.end(); it++)
    	{
    		if (*it == 5)
    		{		
    			printf("%x\n", it);
    			vector<int>::iterator tmp = v1.erase(it); //注意以后开发中编译器版本问题
    			printf("%x,%x\n",it,tmp);
    		}
    	}
    
    	//插入
    	v1.insert(v1.begin() + 2, 100);
    	v1.insert(v1.end() - 1, 200);
    
    	printVector(v1);
    
    	system("pause");
    }
    
    //双向队列
    #include <deque>
    void printDeque(deque<int>& q)
    {
    	for (int i = 0; i < q.size(); i++)
    	{
    		cout << q[i] << endl;
    	}
    }
    
    void main()
    {
    	deque<int> d1;
    	//添加到尾部
    	d1.push_back(2);
    	d1.push_back(10);
    	//添加到头部
    	d1.push_front(-90);
    	d1.push_front(-30);	
    
    	//printDeque(d1);
    
    	//cout << d1.front() << endl;
    	//cout << d1.back() << endl;
    
    	//两个方向弹出
    	//d1.pop_back();
    	//d1.pop_front();
    
    	printDeque(d1);
    
    	//查找第一个-90元素索引位置，无需遍历
    	deque<int>::iterator it = find(d1.begin(),d1.end(),-90);
    	if (it != d1.end())
    	{
    		int idx = distance(d1.begin(), it);
    		cout << "索引位置为：" << idx << endl;
    	}
    
    
    	system("pause");
    }
    
    //数据结构 算法 分离
    //Collections.shuff sort

#define _CRT_SECURE_NO_WARNINGS
    
    #include <iostream>
    #include <queue>
    using namespace std;
    
    //队列（没有迭代器）
    /*
    void main()
    {
    	queue<int> q;
    	q.push(78);
    	q.push(18);
    	q.push(20);
    	q.push(33);
    	
    	//q.front();
    	//q.back();
    	while (!q.empty())
    	{
    		int tmp = q.front();
    		cout << tmp << endl;
    		q.pop();
    	}	
    	system("pause");
    }
    */
    
    //优先级队列
    /*
    #include <functional>
    
    void main()
    {
    	//默认 最大值优先级
    	priority_queue<int> pq1;
    	pq1.push(12);
    	pq1.push(3);
    	pq1.push(40);
    	pq1.push(15);
    
    	while (!pq1.empty())
    	{
    		int tmp = pq1.top();
    		cout << tmp << endl;
    		pq1.pop();
    	}
    
    	cout << "----------" << endl;
    	//最小值优先级队列
    	priority_queue<int, vector<int>,greater<int>> pq2;
    	pq2.push(12);
    	pq2.push(3);
    	pq2.push(40);
    	pq2.push(15);
    
    	while (!pq2.empty())
    	{
    		int tmp = pq2.top();
    		cout << tmp << endl;
    		pq2.pop();
    	}
    
    	system("pause");
    }
    */
    
    //栈
    /*
    #include <stack>
    void main()
    {
    	stack<int> s;
    	for (int i = 0; i < 10; i++)
    	{
    		s.push(i+1);
    	}
    	
    	while (!s.empty())
    	{
    		int tmp = s.top();
    		cout << tmp << endl;
    		s.pop();
    	}
    	
    	system("pause");
    }
    */
    
    //list
    #include <list>
    void printList(list<int>& lst)
    {
    	//迭代器
    	//没有重载“<”运算符
    	for (list<int>::iterator it = lst.begin(); it != lst.end(); it++)
    	{
    		cout << *it << endl;
    	}
    }
    //基本操作
    /*
    void main()
    {
    	list<int> lst;
    	for (int i = 0; i < 10; i++)
    	{
    		//尾部插入元素
    		lst.push_back(i);
    	}
    
    	//头部插入元素
    	lst.push_front(80);
    	lst.push_front(90);
    
    	list<int>::iterator it = lst.begin();
    	it++;
    	cout << *it << endl;
    	//it = it + 3; 注意：不支持随机访问		
    
    	printList(lst);
    
    	system("pause");
    }
    */
    
    
    //删除
    /*
    void main()
    {
    	list<int> lst;
    	for (int i = 0; i < 10; i++)
    	{
    		//尾部插入元素
    		lst.push_back(i);
    	}
    
    	list<int>::iterator it = lst.begin();
    	//删除
    	it++;
    	//删除第二个元素
    	//lst.erase(it);
    
    	//删除区间（已经被删除了元素不能再删除）
    	list<int>::iterator it_begin = lst.begin();
    	list<int>::iterator it_end = lst.begin();
    	it_end++;
    	it_end++;
    	it_end++;
    	lst.erase(it_begin, it_end);
    
    	//直接根据内容删除元素
    	lst.remove(5);
    
    	printList(lst);
    
    	system("pause");
    }
    */
    
    //list插入（应用：频繁的修改）
    //vector（应用：随机访问v[100]）
    /*
    void main()
    {
    	list<int> lst;
    	for (int i = 0; i < 10; i++)
    	{
    		//尾部插入元素
    		lst.push_back(i);
    	}
    
    	list<int>::iterator it = lst.begin();
    	it++;
    	lst.insert(it, 100);
    
    	printList(lst);
    	system("pause");
    }
    */
    
    //set 元素唯一 默认从小到大
    #include <set>
    
    void printSet(set<int> &s)
    {
    	for (set<int>::iterator it = s.begin(); it != s.end(); it++)
    	{
    		cout << *it << endl;
    	}
    }
    /*
    void main()
    {
    	set<int> s;
    	//添加元素
    	for (int i = 0; i < 10; i++)
    	{
    		s.insert(i+1);
    	}
    	s.insert(20);
    	s.insert(15);
    	s.insert(15);
    
    	//删除
    	set<int>::iterator it = s.begin();
    	it++;
    	s.erase(it);	
    
    	printSet(s);
    	system("pause");
    }
    */
    
    //元素按照从大到小排列
    /*
    #include <functional>
    void main()
    {
    	//同Java中：Map<String,List<String>> 
    	set<int,greater<int>> s;
    	s.insert(10);
    	s.insert(5);
    	s.insert(20);
    	s.insert(99);
    
    	for (set<int,greater<int>>::iterator it = s.begin(); it != s.end(); it++)
    	{
    		cout << *it << endl;
    	}
    
    	system("pause");
    }
    */
    
    //元素类型为Teacher对象，按照年龄排序
    /*
    class Teacher
    {
    public:
    	Teacher(char* name, int age)
    	{
    		this->name = name;
    		this->age = age;
    	}
    
    	void print()
    	{
    		cout << name << "," << age << endl;
    	}	
    
    public:
    	char* name;
    	int age;
    };
    
    //自定义排序规则
    //仿函数
    struct MyAgeSorter
    {
    	bool operator()(const Teacher &left, const Teacher &right)
    	{
    		return left.age < right.age;
    	}
    };
    
    void main()
    {
    	set<Teacher, MyAgeSorter> s;
    	s.insert(Teacher("jack",18));
    	s.insert(Teacher("rose", 20));
    	s.insert(Teacher("jason", 22));
    	s.insert(Teacher("alan", 5));
    	//s.insert(Teacher("jimy", 5)); //不会插入
    
    	for (set<Teacher>::iterator it = s.begin(); it != s.end(); it++)
    	{
    		cout << (*it).name << "," << (*it).age << endl;
    	}
    
    	system("pause");
    }
    */
    
    //set查找
    /*
    void main()
    {
    	set<int> s;
    	//添加元素
    	for (int i = 0; i < 10; i++)
    	{
    		s.insert(i + 1);
    	}
    
    	//printSet(s);
    
    	//等于4的元素指针
    	set<int>::iterator s_4 = s.lower_bound(4); 
    	//cout << *s_4 << endl;
    	//大于4的元素指针
    	set<int>::iterator s_5 = s.upper_bound(4);
    	//cout << *s_5 << endl;
    
    	//一次性获取等于4的元素指针，和大于4的元素指针\
    	//BasicNameValuePair
    	pair<set<int>::iterator, set<int>::iterator> p = s.equal_range(4);
    	cout << *p.first << endl;
    	cout << *p.second << endl;
    	system("pause");
    }
    */
    
    
    //multiset 允许重复的元素
    /*
    void main()
    {
    	multiset<int> s;
    	s.insert(2);
    	s.insert(8);
    	s.insert(2);
    	s.insert(8);
    
    	for (multiset<int>::iterator it = s.begin(); it != s.end(); it++)
    	{
    		cout <<  *it << endl;
    	}
    
    	system("pause");
    }
    */
    
    
    //map添加元素的方式
    #include <map>
    #include <string>
    /*
    void main()
    {
    	//key -> value
    	//1.
    	map<int, string> map1;
    	map1.insert(pair<int, string>(1,"jack"));
    	map1.insert(pair<int, string>(2, "rose"));
    
    	//2
    	map1.insert(make_pair(3,"jason"));
    
    	//3
    	map1.insert(map<int,string>::value_type(4,"alan"));
    
    	//4
    	map1[5] = "jimmy"; //map["NO1"] = 90;
    
    	//前三种方式，如果key已经存在，重复添加会报错
    	//第四种方式，如果key已经存在，重复添加会覆盖
    	
    	//遍历输出
    	for (map<int, string>::iterator it = map1.begin(); it != map1.end(); it++)
    	{
    		cout << it->first << "," << it->second << endl;		
    	}
    
    
    	system("pause");
    }
    
    */
    
    void printMap(map<int, string> &map1)
    {
    	for (map<int, string>::iterator it = map1.begin(); it != map1.end(); it++)
    	{
    		cout << it->first << "," << it->second << endl;
    	}
    }
    
    //删除
    /*
    void main()
    {
    	map<int, string> map1;
    	map1.insert(pair<int, string>(1, "jack"));
    	map1.insert(pair<int, string>(2, "rose"));
    	map1.insert(pair<int, string>(3, "jason"));	
    
    	map<int, string>::iterator it = map1.begin();
    	it++;
    	map1.erase(it);
    
    	printMap(map1);
    
    	system("pause");
    }
    */
    
    //添加的结果
    /*
    void main()
    {
    	map<int, string> map1;
    	map1.insert(pair<int, string>(1, "jack"));
    	map1.insert(pair<int, string>(2, "rose"));
    	map1.insert(pair<int, string>(3, "jason"));
    	//获取添加的结果（first元素指针，second 是否成功）
    	pair<map<int, string>::iterator, bool> res = map1.insert(pair<int, string>(3, "alan"));
    	if (res.second)
    	{
    		cout << "添加成功" << endl;
    	}
    	else
    	{
    		cout << "添加失败" << endl;
    	}
    
    	printMap(map1);
    
    	system("pause");
    }
    */
    
    
    //查找
    /*
    void main()
    {
    	map<int, string> map1;
    	map1.insert(pair<int, string>(1, "jack"));
    	map1.insert(pair<int, string>(2, "rose"));
    	map1.insert(pair<int, string>(3, "jason"));	
    
    	printMap(map1);
    
    	cout << "---------" << endl;
    
    	//获取key等于大于5的元素的值
    	pair<map<int, string>::iterator, map<int, string>::iterator> p = map1.equal_range(2);
    	if (p.first != map1.end()){
    		//等于2的元素key value
    		cout << p.first->first << p.first->second << endl;
    
    		//大于2的元素key value
    		cout << p.second->first << p.second->second << endl;
    	}
    
    	system("pause");
    }
    */
    
    //一个key对应多个value
    //一个部门多个员工
    //multimap
    /*
    class Employee
    {
    public:
    	Employee(char* name,int age)
    	{
    		this->name = name;
    		this->age = age;
    	}
    
    public:
    	char* name;
    	int age;
    };
    
    void main()
    {
    	multimap<string, Employee> map1;
    	
    	//开发部
    	map1.insert(make_pair("开发", Employee("搁浅", 20)));
    	map1.insert(make_pair("开发", Employee("彪哥", 20)));
    
    	//财务
    	map1.insert(make_pair("财务", Employee("小颖", 16)));
    	map1.insert(make_pair("财务", Employee("rose", 20)));
    
    	//销售
    	map1.insert(make_pair("销售", Employee("阿呆", 30)));
    	map1.insert(make_pair("销售", Employee("呵呵", 30)));
    
    	//遍历输出
    	for (multimap<string, Employee>::iterator it = map1.begin(); it != map1.end(); it++)
    	{
    		cout << it->first << "," << it->second.name  << "," << it->second.age << endl;
    	}
    
    	cout << "----------------" << endl;
    	//只获取“财务”部的员工
    	//获取“财务部”员工的个数，key对应的value的个数
    	int num = map1.count("财务");
    	multimap<string, Employee>::iterator it = map1.find("财务");
    	int c = 0; //控制循环的次数
    	while (it != map1.end() && c < num)
    	{		
    		cout << it->first << "," << it->second.name << "," << it->second.age << endl;
    		it++;
    		c++;
    	}
    
    	system("pause");
    }
    */
    
    //深拷贝与浅拷贝
    /*
    class Employee
    {
    public:
    	//构造函数
    	Employee(char* name, int age)
    	{		
    		this->name = new char[strlen(name) + 1];
    		strcpy(this->name, name);
    		this->age = age;
    	}
    
    	//析构函数
    	~Employee()
    	{
    		if (this->name != NULL)
    		{
    			delete[] this->name;
    			this->name = NULL;
    			this->age = 0;
    		}
    	}
    	//拷贝构造函数
    	//Employee e = 
    	Employee(const Employee &obj)
    	{
    		this->name = new char[strlen(obj.name) + 1];
    		strcpy(this->name, obj.name);
    		this->age = obj.age;
    	}
    
    	//重载=
    	//e1 = e2;
    	Employee& operator=(const Employee &obj)
    	{
    		//释放旧的内存
    		if (this->name != NULL)
    		{
    			delete[] this->name;
    			this->name = NULL;
    			this->age = 0;
    		}
    
    		//重新分配
    		this->name = new char[strlen(obj.name) + 1];
    		strcpy(this->name, obj.name);
    		this->age = obj.age;
    
    		return *this;
    	}
    
    public:	
    	char* name;
    	int age;
    };
    
    void func()
    {
    	vector<Employee> v1;
    	Employee e1("jack",20);	
    	v1.push_back(e1);
    }
    
    void main()
    {
    	//vector<Employee> v1;
    	//Employee e1("jack",20);
    	//将e1拷贝到vector中
    	//v1.push_back(e1);
    
    	func();
    
    	system("pause");
    }
    */

标准模板库的一些函数

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