std::allocator::max_size
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                    | size_type max_size() const; | (deprecated since C++17) | |
Returns the maximum theoretically possible value of n, for which the call allocate(n, 0) could succeed. 
In most implementations, this returns std::numeric_limits<size_type>::max() / sizeof(value_type).
Parameters
(none)
Return value
The maximum supported allocation size
Exceptions
| (none) | (until C++11) | 
| noexcept specification:   noexcept | (since C++11) | 
See also
| [static] | returns the maximum object size supported by the allocator (public static member function of std::allocator_traits) |