vector系列--assign() push_back() or insert()应用示例

实际应用

// inserting into a vector
#include <iostream>
#include <vector>

int main ()
{
  std::vector<int> myvector (3,100);
  std::vector<int>::iterator it;

  it = myvector.begin();
  it = myvector.insert ( it , 200 );

  myvector.insert (it,2,300);

  // "it" no longer valid, get a new one:
  it = myvector.begin();

  std::vector<int> anothervector (2,400);
  myvector.insert (it+2,anothervector.begin(),anothervector.end());

  int myarray [] = { 501,502,503 };
  myvector.insert (myvector.begin(), myarray, myarray+3);

  std::cout << "myvector contains:";
  for (it=myvector.begin(); it<myvector.end(); it++)
    std::cout << ' ' << *it;
  std::cout << '
';

  return 0;
}

//输出：
myvector contains: 501 502 503 300 300 400 400 200 100 100 100

　　

assign vs insert
只有当vector为空的时候，assign和insert是相同的。

如果vetor是空的，使用assign更好。