blob: 910b7e455af11b635508fba213ea5c1a850fafe6 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
|
.. highlight:: cpp
.. _lang-unsignedlonglong:
``unsigned long long``
======================
An unsigned version of the :ref:`long long <lang-longlong>` data type.
An ``unsigned long long`` occupies 8 bytes of memory; it stores an
integer from 0 to 2^64-1, which is approximately 1.8×10^19 (18
quintillion, or 18 billion billion).
A synonym for the ``unsigned long long`` type is ``uint64``.
Like an :ref:`unsigned int <lang-unsignedint>`, an ``unsigned long
long`` won't store negative numbers; it is also subject to the same
:ref:`overflow issues <lang-int-overflow>` as any integral data type.
Here is an example of declaring an ``unsigned long long`` variable
named ``c``, then giving it value 299,792,458,000,000,000 (see
:ref:`integer constants <lang-constants-integers-u-l>` for an
explanation of the "ULL" at the end of the number)::
// Speed of light in nanometers per second (approximate).
unsigned long long c = 299792458000000000ULL;
The general syntax for declaring an ``unsigned long long`` variable named
``var``, then giving it value ``val``, looks like::
unsigned long long var = val;
See Also
--------
- :ref:`long long <lang-longlong>`
- :ref:`int <lang-int>`
- :ref:`unsigned <lang-unsignedint>`
- :ref:`char <lang-char>`
- :ref:`unsigned char <lang-unsignedchar>`
- :ref:`Integer Constants <lang-constants-integers>`
- :ref:`Variables <lang-variables>`
.. include:: cc-attribution.txt
|
