C++中vector的简单用法

1.vector 的数据的存入和输出：

#include<stdio.h>
#include<vector>
#include <iostream>

using namespace std;

void main()

{

   int i = 0;

    vector<int> v;

    for( i = 0; i < 10; i++ )

   {

             v.push_back( i );//把元素一个一个存入到vector中

   }

   for( i = 0; i < v.size(); i++ )//v.size() 表示vector存入元素的个数

   {

          cout << v[ i ] << "  "; //把每个元素显示出来

   }

   cont << endl;

} 

注：你也可以用v.begin()和v.end() 来得到vector开始的和结束的元素地址的指针位置。你也可以这样做：

vector<int>::iterator iter;

for( iter = v.begin(); iter != v.end(); iter++ )

{
    cout << *iter << endl;
}

2. 对于二维vector的定义。

1)定义一个10个vector元素，并对每个vector符值1-10。

#include<stdio.h>
#include<vector>
#include <iostream>

using namespace std;

void main()
{
 int i = 0, j = 0;

//定义一个二维的动态数组，有10行，每一行是一个用一个vector存储这一行的数据。

所以每一行的长度是可以变化的。之所以用到vector<int>(0)是对vector初始化，否则不能对vector存入元素。
 vector< vector<int> > Array( 10, vector<int>(0) ); 

for( j = 0; j < 10; j++ )
 {
  for ( i = 0; i < 9; i++ )
  {
   Array[ j ].push_back( i );
  }
 }

 for( j = 0; j < 10; j++ )
 {
  for( i = 0; i < Array[ j ].size(); i++ )
  {
   cout << Array[ j ][ i ] << "  ";
  }
  cout<< endl;
 }
}

2)定义一个行列都是变化的数组。

#include<stdio.h>
#include<vector>
#include <iostream>

using namespace std;

void main()
{
 int i = 0, j = 0;

 vector< vector<int> > Array;
 vector< int > line;
 for( j = 0; j < 10; j++ )
 {
  Array.push_back( line );//要对每一个vector初始化，否则不能存入元素。
  for ( i = 0; i < 9; i++ )
  {
   Array[ j ].push_back( i );
  }
 }

 for( j = 0; j < 10; j++ )
 {
  for( i = 0; i < Array[ j ].size(); i++ )
  {
   cout << Array[ j ][ i ] << "  ";
  }
  cout<< endl;
 }
}
                                                                                  -----zz自 http://blog.youkuaiyun.com/tjh666/archive/2007/05/11/1604119.aspx


下面是我找的一些常用vector类的成员函数~

push_back()插入一个元素
pop_back() 可以弹出最后ch一个元素
erase(iterator   it)可以删除指定位置的元素
size（）求vector中的已存的元素个数
clear（）可以清空vector中的元素

Vector constructors	create vectors and initialize them with some data
Vector operators	compare, assign, and access elements of a vector
assign	assign elements to a vector
at	returns an element at a specific location
back	returns a reference to last element of a vector
begin	returns an iterator to the beginning of the vector
capacity	returns the number of elements that the vector can hold
clear	removes all elements from the vector
empty	true if the vector has no elements
end	returns an iterator just past the last element of a vector
erase	removes elements from a vector
front	returns a reference to the first element of a vector
insert	inserts elements into the vector
max_size	returns the maximum number of elements that the vector can hold
pop_back	removes the last element of a vector
push_back	add an element to the end of the vector
rbegin	returns a reverse_iterator to the end of the vector
rend	returns a reverse_iterator to the beginning of the vector
reserve	sets the minimum capacity of the vector
resize	change the size of the vector
size	returns the number of items in the vector
swap	swap the contents of this vector with another