C++ list::insert

原文
mylist.insert (it,10)
会在mylist的it迭代器之前插入10
可选参数n
mylist.insert (it,n,20);
则会在it前插入n个20

// inserting into a list
#include <iostream>
#include <list>
#include <vector>
using namespace std;
int main ()
{
  list<int> mylist;
  list<int>::iterator it;
  // set some initial values:
  for (int i=1; i<=5; ++i) mylist.push_back(i); // 1 2 3 4 5
  it = mylist.begin();
  ++it;       // it points now to number 2           ^
  mylist.insert (it,10);                        // 1 10 2 3 4 5
  // "it" still points to number 2                      ^
  mylist.insert (it,2,20);                      // 1 10 20 20 2 3 4 5
  --it;       // it points now to the second 20            ^
  vector<int> myvector (2,30);
  mylist.insert (it,myvector.begin(),myvector.end());
                                                // 1 10 20 30 30 20 2 3 4 5
                                                //               ^
  cout << "mylist contains:";
  for (it=mylist.begin(); it!=mylist.end(); ++it)
    cout << ' ' << *it;
  cout << '\n';
  return 0;
}