STL中Vector的使用方法详解

// VectorDemo.cpp : 定义控制台应用程序的入口点。
//Visual C++ 6.0 中编译通过

# include <iostream>
# include <vector>

using namespace std;

typedef vector<int> INTVECTOR;

void PrintIntVector(INTVECTOR iVector)
{
//遍历vector方法
cout<<"Vector: [";
for(INTVECTOR::iterator it = iVector.begin(); it != iVector.end(); it++)
{
cout<<*it;
if(it != iVector.end()-1)
{
cout<<",";
}
}
cout<<"]"<<endl;
}
int main(int argc, char* argv[])
{
INTVECTOR iVector;
//push_back方法
iVector.push_back(2);
iVector.push_back(3);
iVector.push_back(4);
iVector.push_back(1);
iVector.push_back(10);
iVector.push_back(20);
PrintIntVector(iVector);
//Vector: [2,3,4,1,10,20]

//pop_back方法
iVector.pop_back();
PrintIntVector(iVector);
//Vector: [2,3,4,1,10]

//size、capacity 与 max_size方法
cout<<"size="<<iVector.size()<<" capacity="<<iVector.capacity()<<" max_size="<<iVector.max_size()<<endl;
//size=5 capacity=6 max_size=1073741823

//reserve方法
iVector.reserve(20);
cout<<"After reserve: size="<<iVector.size()<<" capacity="<<iVector.capacity()<<" max_size="<<iVector.max_size()<<endl;
//After reserve: size=5 capacity=20 max_size=1073741823

//resize方法
iVector.resize(100);
cout<<"After resize: size="<<iVector.size()<<" capacity="<<iVector.capacity()<<" max_size="<<iVector.max_size()<<endl;
//After resize: size=100 capacity=100 max_size=1073741823

//begin方法
iVector.resize(5);//修改为5
INTVECTOR::iterator iter;
iter = iVector.begin();
cout<<"First element:"<<*iter<<endl;
//First element:2

//insert方法
//PrintIntVector(iVector);
iter = iVector.insert(iter, 65);
iVector.insert(iter+1, 2, 30);
iVector.insert(iVector.end(), iVector.begin(), iVector.end());//复制
PrintIntVector(iVector);
//Vector: [65,30,30,2,3,4,1,10,65,30,30,2,3,4,1,10]

//at方法
cout<<"Fifth element:"<<iVector.at(4)<<endl;
//Fifth element:3

//front 和 back方法
cout<<"First element: "<<iVector.front()<< endl;
cout<<"Last element: "<<iVector.back()<< endl;
//First element: 65
//Last element: 10

//erase方法
iVector.erase(iVector.begin());
PrintIntVector(iVector);
//Vector: [30,30,2,3,4,1,10,65,30,30,2,3,4,1,10]

//reverse_iterator使用方法
INTVECTOR::reverse_iterator riter;
riter = iVector.rbegin();
cout<<"Last element: "<<(*riter)<<endl;
riter = iVector.rend();
cout<<"First element: "<<*(riter-1)<<endl;
//Last element: 10
//First element: 30

//随机访问方法
cout<<"Eleventh element:"<<iVector[10]<<endl;
//Eleventh element:2

//clear方法
iVector.clear();
PrintIntVector(iVector);
//Vector: []

return 0;
}

所有输出：

Vector: [2,3,4,1,10,20]
Vector: [2,3,4,1,10]
size=5 capacity=6 max_size=1073741823
After reserve: size=5 capacity=20 max_size=1073741823
After resize: size=100 capacity=100 max_size=1073741823
First element:2
Vector: [65,30,30,2,3,4,1,10,65,30,30,2,3,4,1,10]
Fifth element:3
First element: 65
Last element: 10
Vector: [30,30,2,3,4,1,10,65,30,30,2,3,4,1,10]
Last element: 10
First element: 30
Eleventh element:2
Vector: []