vector insert

1vector<int> a;
2vector<int> b;
3// Appending the integers of b to the end of a 
4a.insert(a.end(), b.begin(), b.end());

1// inserting into a vector
2#include <iostream>
3#include <vector>
4
5int main ()
6{
7  std::vector<int> myvector (3,100);
8  std::vector<int>::iterator it;
9
10  it = myvector.begin();
11  it = myvector.insert ( it , 200 );
12
13  myvector.insert (it,2,300);
14
15  // "it" no longer valid, get a new one:
16  it = myvector.begin();
17
18  std::vector<int> anothervector (2,400);
19  myvector.insert (it+2,anothervector.begin(),anothervector.end());
20
21  int myarray [] = { 501,502,503 };
22  myvector.insert (myvector.begin(), myarray, myarray+3);
23
24  std::cout << "myvector contains:";
25  for (it=myvector.begin(); it<myvector.end(); it++)
26    std::cout << ' ' << *it;
27  std::cout << '\n';
28
29  return 0;
30}

1#include <iostream>
2#include <vector>
3 
4void print_vec(const std::vector<int>& vec)
5{
6    for (auto x: vec) {
7         std::cout << ' ' << x;
8    }
9    std::cout << '\n';
10}
11 
12int main ()
13{
14    std::vector<int> vec(3,100);
15    print_vec(vec);
16 
17    auto it = vec.begin();
18    it = vec.insert(it, 200);
19    print_vec(vec);
20 
21    vec.insert(it,2,300);
22    print_vec(vec);
23 
24    // "it" no longer valid, get a new one:
25    it = vec.begin();
26 
27    std::vector<int> vec2(2,400);
28    vec.insert(it+2, vec2.begin(), vec2.end());
29    print_vec(vec);
30 
31    int arr[] = { 501,502,503 };
32    vec.insert(vec.begin(), arr, arr+3);
33    print_vec(vec);
34}