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# std::unordered_set::max_size

From cppreference.com
< cpp‎ | container‎ | unordered set

[edit template]

size_type max_size() const; |  | (since C++11)

Returns the maximum number of elements the container is able to hold due to system or library implementation limitations, i.e. std::distance(begin(), end()) for the largest container.

### [edit] Parameters

(none)

### [edit] Return value

Maximum number of elements.

### [edit] Exceptions

`noexcept` specification:
noexcept

### [edit] Complexity

Constant.

### [edit] Notes

This value typically reflects the theoretical limit on the size of the container. At runtime, the size of the container may be limited to a value smaller than `max_size()` by the amount of RAM available.

### [edit] Example

Run this code

    #include <iostream>
    #include <unordered_set>

    int main()
    {
        std::unordered_set<char> s;
        std::cout << "Maximum size of a 'unordered_set' is " << s.max_size() << "\n";
    }

Possible output:

    Maximum size of a 'unordered_set' is 18446744073709551615

### See also

size | returns the number of elements (public member function) [edit]

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