Namespaces
Variants
Views
Actions

Difference between revisions of "cpp/container/vector/max size"

From cppreference.com
< cpp‎ | container‎ | vector
m (Shorten template names. Use {{lc}} where appropriate.)
m (langlinks)
 
Line 1: Line 1:
 
{{include page|cpp/container/max_size|vector}}
 
{{include page|cpp/container/max_size|vector}}
  
[[de:cpp/container/vector/max size]]
+
{{langlinks|de|es|fr|it|ja|pl|pt|ru|zh}}
[[es:cpp/container/vector/max size]]
+
[[fr:cpp/container/vector/max size]]
+
[[it:cpp/container/vector/max size]]
+
[[ja:cpp/container/vector/max size]]
+
[[pt:cpp/container/vector/max size]]
+
[[ru:cpp/container/vector/max size]]
+
[[zh:cpp/container/vector/max size]]
+

Latest revision as of 07:13, 7 November 2021

 
 
 
 
size_type max_size() const;
(noexcept since C++11)
(constexpr since C++20)

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.

Contents

[edit] Parameters

(none)

[edit] Return value

Maximum number of elements.

[edit] Complexity

Constant.

[edit] Notes

This value typically reflects the theoretical limit on the size of the container, at most std::numeric_limits<difference_type>::max(). 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

#include <iostream>
#include <locale>
#include <vector>
 
int main()
{
    std::vector<char> p;
    std::vector<long> q;
 
    std::cout.imbue(std::locale("en_US.UTF-8"));
    std::cout << std::uppercase
              << "p.max_size() = " << std::dec << p.max_size() << " = 0x"
              << std::hex << p.max_size() << '\n'
              << "q.max_size() = " << std::dec << q.max_size() << " = 0x"
              << std::hex << q.max_size() << '\n';
}

Possible output:

p.max_size() = 9,223,372,036,854,775,807 = 0x7,FFF,FFF,FFF,FFF,FFF
q.max_size() = 1,152,921,504,606,846,975 = 0xFFF,FFF,FFF,FFF,FFF

See also

returns the number of elements
(public member function) [edit]
returns the number of elements that can be held in currently allocated storage
(public member function) [edit]