vector::clear ，vector::crbegin （c++11），vector::crend（c++11）

vector::clear

// clearing vectors
#include <iostream>
#include <vector>
using namespace std;
int main ()
{
  vector<int> myvector;
  myvector.push_back (100);
  myvector.push_back (200);
  myvector.push_back (300);

  cout << "myvector contains:";
  for (unsigned i=0; i<myvector.size(); i++)
    cout << ' ' << myvector[i];
  cout << '\n';

  myvector.clear(); //清除了容器里的内存 
  myvector.push_back (1101);
  myvector.push_back (2202);

  cout << "myvector contains:";
  for (unsigned i=0; i<myvector.size(); i++)
    cout << ' ' << myvector[i];
     cout << '\n';

  return 0;
}

vector::crbegin

（C++ 11）

// vector::crbegin/crend
#include <iostream>
#include <vector>
using namespace std; 
int main ()
{
  vector<int> myvector = {1,2,3,4,5};
  cout << "myvector backwards:";
  for (auto rit = myvector.crbegin(); rit != myvector.crend(); ++rit)
    cout << ' ' << *rit;
    cout << '\n';
  return 0;
}

Return Value

A const_reverse_iterator to the reverse beginning of the sequence.

Output:

vector::crend

同上。