map::max_size


public member function
size_type max_size () const;

Return maximum size

Returns the maximum number of elements that the map container object can hold.

This is the maximum potential size the container can reach due to system or library implementation limitations.

Parameters

none

Return Value

The maximum number of elements a map container can have as its content.

Member type size_type is an unsigned integral type.

Example

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// map::max_size
#include <iostream>
#include <map>
using namespace std;

int main ()
{
  int i;
  map<int,int> mymap;

  if (mymap.max_size()>1000)
  {
    for (i=0; i<1000; i++) mymap[i]=0;
    cout << "The map contains 1000 elements.\n";
  }
  else cout << "The map could not hold 1000 elements.\n";

  return 0;
}


Here, member max_size is used to check beforehand whether the map will allow for 1000 elements to be inserted.

Complexity

Constant.

See also

map::size Return container size (public member function)