c++ vector 实战（基本使用）

1.pop_back()&push_back(elem)实例在容器最后移除和插入数据

#include <string.h>
#include <vector>
#include <iostream>
using namespace std;

int main()
{
    vector<int>obj;//创建一个向量存储容器 int
    for (int i = 0; i < 10; i++) // push_back(elem)在数组最后添加数据 
    {
        obj.push_back(i);
        cout << obj[i] << ",";
    }

    for (int i = 0; i < 5; i++)//去掉数组最后一个数据 
    {
        obj.pop_back();
    }

    cout << "\n" << endl;

    for (int i = 0; i < obj.size(); i++)//size()容器中实际数据个数 
    {
        cout << obj[i] << ",";
    }

    return 0;
}

0,1,2,3,4,5,6,7,8,9,

0,1,2,3,4,

2.clear()清除容器中所有数据

#include <string.h>
#include <vector>
#include <iostream>
using namespace std;

int main()
{
    vector<int>obj;
    for (int i = 0; i < 10; i++)//push_back(elem)在数组最后添加数据 
    {
        obj.push_back(i);
        cout << obj[i] << ",";
    }

    obj.clear();//清除容器中所以数据
    for (int i = 0; i < obj.size(); i++)
    {
        cout << obj[i] << endl;
    }

    return 0;
}

0,1,2,3,4,5,6,7,8,9,

3.排序

#include <string.h>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
 
int main()
{
    vector<int>obj;
 
    obj.push_back(1);
    obj.push_back(3);
    obj.push_back(0);
 
    sort(obj.begin(),obj.end());//从小到大
 
    cout<<"从小到大:"<<endl;
    for(int i=0;i<obj.size();i++)
    {
        cout<<obj[i]<<",";  
    } 
 
    cout<<"\n"<<endl;
 
    cout<<"从大到小:"<<endl;
    reverse(obj.begin(),obj.end());//从大到小 
    for(int i=0;i<obj.size();i++)
    {
        cout<<obj[i]<<",";
    }
    return 0;
}

从小到大:
0,1,3,

从大到小:
3,1,0,