unordered_multiset max_size in C++ STL

The max_size() of unordered_multiset takes the maximum number of elements that the unordered_multiset container is able to hold due to system or It gets the maximum size of the controlled sequence.


size_type max_size() const;

where size_type is an unsigned integral type.

Returns : The member function returns the length of the longest sequence that the object can hold. In short, the maximum number of elements.

Below program illustrate the unordered_multiset max_size function :-

Example 1:





#include <iostream>
#include <unordered_set>
using namespace std;
int main()
    // Define the unordered_set
    unordered_multiset<int> num{ 1, 2, 3, 4, 5, 6 };
    cout << "Maximum size = "
         << num.max_size() << "\n";
    cout << "Current size = "
         << num.size();
    return 0;



Maximum size = 1152921504606846975
Current size = 6

Complexity :
It takes constant(O(1)) time of complexity to perform an operation.

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