vector::swap


public member function
void swap ( vector<T,Allocator>& vec );

Swap content

Exchanges the content of the vector by the content of vec, which is another vector of the same type. Sizes may differ.

After the call to this member function, the elements in this container are those which were in vec before the call, and the elements of vec are those which were in this. All iterators, references and pointers remain valid for the swapped vectors.

Notice that a global algorithm function exists with this same name, swap, and the same behavior.

Parameters

vec
Another vector container of the same type as this whose content is swapped with that of this container.


Return value

none

Example

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// swap vectors
#include <iostream>
#include <vector>
using namespace std;

main ()
{
  unsigned int i;
  vector<int> first (3,100);   // three ints with a value of 100
  vector<int> second (5,200);  // five ints with a value of 200

  first.swap(second);

  cout << "first contains:";
  for (i=0; i<first.size(); i++) cout << " " << first[i];

  cout << "\nsecond contains:";
  for (i=0; i<second.size(); i++) cout << " " << second[i];

  cout << endl;

  return 0;
}


Output:
first contains: 200 200 200 200 200 
second contains: 100 100 100


Complexity

Constant.

See also

swap Exchange values of two objects (function template)