C++ Standard Library C++ STL Library

C++ <deque> - max_size() Function



The C++ deque::max_size function returns the maximum size the deque can reach. The function returns the maximum potential size the deque can reach due to known system or library implementation limitations.

Syntax

size_type max_size() const;
size_type max_size() const noexcept;

Parameters

No parameter is required.

Return Value

Maximum number of elements that can be held in a deque.

Time Complexity

Constant i.e, Θ(1).

Example:

In the example below, the deque::max_size function is used find out the maximum number of elements that a deque can hold.

#include <iostream>
#include <deque>
using namespace std;
 
int main (){
  deque<int> MyDeque{10, 20, 30, 40, 50};
  deque<int>::iterator it;

  cout<<"The deque contains:";
  for(it = MyDeque.begin(); it != MyDeque.end(); ++it)
    cout<<" "<<*it;
    
  cout<<"\nDeque size is: "<<MyDeque.size()<<"\n";
  cout<<"Maximum size of the Deque: "<<MyDeque.max_size()<<"\n"; 
  return 0;
}

A possible output could be:

The deque contains: 10 20 30 40 50
Deque size is: 5
Maximum size of the Deque: 2305843009213693951

❮ C++ <deque> Library