vector::insert， vector::max_size, vector::operator=

vector::insert

// vector::get_allocator
#include <iostream>
#include <vector>
using namespace std;
int main ()
{
vector<int> myvector (3,100); //原始
vector<int>::iterator it;

it = myvector.begin();
it = myvector.insert ( it , 200 ); // 插入100

myvector.insert (it,2,300); //插入 2个200
// "it" no longer valid, get a new one: it = myvector.begin();
vector<int> anothervector (2,400);
myvector.insert (it+2,anothervector.begin(),anothervector.end()); //插入2个400

int myarray [] = { 501,502,503 };
myvector.insert (myvector.begin(), myarray, myarray+3); //插入这个数组中的数据

std::cout << "myvector contains:";
for (it=myvector.begin(); it<myvector.end(); it++)
cout << ' ' << *it;
cout << '\n';
return 0;
}
//Output:
//myvector contains: 501 502 503 300 300 400 400 200 100 100 100

vector::max_size

// comparing size, capacity and max_size
#include <iostream>
#include <vector>
using namespace std;
int main ()
{
vector<int> myvector;

// set some content in the vector:
for (int i=0; i<100; i++) myvector.push_back(i);
cout << "size: " << myvector.size() << "\n";
cout << "capacity: " << myvector.capacity() << "\n";
cout << "max_size: " << myvector.max_size() << "\n";
return 0;
}
/*
A possible output for this program could be:
size: 100
capacity: 128
max_size: 1073741823
*/

vector::operator=

// vector assignment
#include <iostream>
#include <vector>
using namespace std;
int main ()
{
vector<int> foo (1314,0);
vector<int> bar (5,0);

bar = foo;
foo = std::vector<int>();

cout << "Size of foo: " << int(foo.size()) << '\n'; //输出 0，之前的空间会被delete
cout << "Size of bar: " << int(bar.size()) << '\n'; //新赋予的空间
return 0;
}
/*
Output:
Size of foo: 0
Size of bar: 1314
*/