STL三大组件

STL三大组件

一、容器

二、算法

三、迭代器

#define _CRT_SECURE_NO_WARNINGS
#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;

//STL 中的容器 算法 迭代器
void test01(){
    
    
	vector<int> v; //STL 中的标准容器之一 ：动态数组
	v.push_back(1); //vector 容器提供的插入数据的方法
	v.push_back(5);
	v.push_back(3);
	v.push_back(7);
	//迭代器
	vector<int>::iterator pStart = v.begin(); //vector 容器提供了 begin()方法 返回指向第一个元素的迭代器
	vector<int>::iterator pEnd = v.end(); //vector 容器提供了 end()方法 返回指向最后一个元素下一个位置的迭代器
	//通过迭代器遍历
	while (pStart != pEnd){
    
    
		cout << *pStart << " ";
		pStart++;
	}
	cout << endl;
}
//STL 容器不单单可以存储基础数据类型，也可以存储类对象
class Teacher
{
    
    
public:
	Teacher(int age) :age(age){
    
    };
	~Teacher(){
    
    };
public:
	int age;
};
void test02(){
    
    
	vector<Teacher> v; //存储 Teacher 类型数据的容器
	Teacher t1(10), t2(20), t3(30);
	v.push_back(t1);
	v.push_back(t2);
	v.push_back(t3);
	vector<Teacher>::iterator pStart = v.begin();
	vector<Teacher>::iterator pEnd = v.end();
	//通过迭代器遍历
	while (pStart != pEnd){
    
    
		cout << pStart->age << " ";
		pStart++;
	}
	cout << endl;
}
//存储 Teacher 类型指针
void test03(){
    
    
	vector<Teacher*> v; //存储 Teacher 类型指针
	Teacher* t1 = new Teacher(10);
	Teacher* t2 = new Teacher(20);
	Teacher* t3 = new Teacher(30);
	v.push_back(t1);
	v.push_back(t2);
	v.push_back(t3);
	//拿到容器迭代器
	vector<Teacher*>::iterator pStart = v.begin();
	vector<Teacher*>::iterator pEnd = v.end();
	//通过迭代器遍历
	while (pStart != pEnd){
    
    
		cout << (*pStart)->age << " ";
		pStart++;
	}
	cout << endl;
}
//容器嵌套容器 难点(不理解，可以跳过)
void test04()
{
    
    
	vector< vector<int> > v;
	vector<int>v1;
	vector<int>v2;
	vector<int>v3;

	for (int i = 0; i < 5;i++)
	{
    
    
		v1.push_back(i);
		v2.push_back(i * 10);
		v3.push_back(i * 100);
	}
	v.push_back(v1);
	v.push_back(v2);
	v.push_back(v3);

	for (vector< vector<int> >::iterator it = v.begin(); it != v.end();it++)
	{
    
    
		for (vector<int>::iterator subIt = (*it).begin(); subIt != (*it).end(); subIt ++)
		{
    
    
			cout << *subIt << " ";
		}
		cout << endl;
	}
} 
int main(){
    
    
	//test01();
	//test02();
	//test03();
	test04();
	system("pause");
	return EXIT_SUCCESS;
}