The `long long` size modifier was introduced in C++11 and can be used with integral types to select an integer of at least 64 bits.
See cppreference for more information.
Questions tagged [long-long]
131 questions
3
votes
2 answers
If on my machine sizeof(long) == sizeof(long long), why aren't they the same type?
If I run:
#include
#include
int main()
{
std::cout << "sizeof(long) = " << sizeof(long) << "\n";
std::cout << "sizeof(long long) = " << sizeof(long long) << "\n";
std::cout << "std::is_same
einpoklum
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3
votes
1 answer
How to bridge a long long C macro to Swift?
In Foundation there is C macro NSURLResponseUnknownLength defined as a long long:
#define NSURLResponseUnknownLength ((long long)-1)
Due to the way macros are bridged to Swift, this constant is accessible in an Objective-C application, but not in a…
JAL
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3
votes
0 answers
Selecting 'long' versus 'long long' as 64-bit type under LP64/ILP64/LLP64 data models?
I'm trying to understand the requirements for selecting a built-in 64-bit data type using either long or long long. I'm having trouble understanding the type equivalence and the alignment requirements of long versus long long.
What is the best…
jww
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3
votes
1 answer
Qt : from unsigned long long to QJsonObject
Is it possible to use long long as a value at QJsonObject ? I was forced to change my API from JSON to XML because 1 field I got had BigInt values and aparently I can't extract big numbers from QJsonValue.
Here's my peace of code that may show what…
Rafael Fontes
- 1,195
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3
votes
1 answer
Is it possible to add -pedantic to GCC command line, yet have it not warn about 'long long'
I'm using mostly GCC to develop my library, but I'd like to ensure cross-compiler compatibility and especially standard conformance as much as possible. For this, I have add several -W... flags to command line. I'd also add -pedantic, but I have a…
user319799
3
votes
2 answers
Accelerating performance of loop performing unsigned long long modulo operation
I need to perform a many operations of finding remainders of the division unsigned long long number by the 16-bit modulus:
unsigned long long largeNumber;
long residues[100];
unsigned long modules[100];
intiModules(modules); //set different 16-bit…
Konstantin Isupov
- 199
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- 12
3
votes
6 answers
confuse in "double to long long" in c++
my code:
int main()
{
long long a = pow(2,63) - 1;
long long b = pow(2,63);
double c = pow(2,63) - 1;
double d = pow(2,63);
printf("%lld %lld \n%f %f \n%lld %lld\n", a, b, c, d, (long long)c, (long long)d);
return 0;
}
and the excute result is…
tenos
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- 16
3
votes
0 answers
Same C code gives different outputs on IDEONE and PC
#include
int main()
{
long long i,j;
for(i = 1,j = 100;i<5000;i+= 50,j+=23)
printf("%lld %lld\n",i,j);
return 0;
}
The output for this code on IDEONE can be seen here : http://ideone.com/YCbc9V
I am using GCC 4.8.1 on…
reb94
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3
votes
3 answers
Objective-C NSNumber numberWithLongLong creates integer
When I attempt to create an NSNumber using the numberWithLongLong with a number greater than -2 and less than 13 it returns a number that is casted as an (int).
I see this if I look at the Xcode debugger after stepping over my line.
NSNumber*…
user1556446
- 33
- 5
3
votes
4 answers
How can I convert from LONGLONG to class _variant_t?
In this example m_Amount is CString. stringToNumber function converts it to a LONGLONG number successfully. But when I want to assign it to a variant I get this error:
error C2440: 'type cast' : cannot convert from '__int64' to 'class…
Bob
- 22,810
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2
votes
5 answers
How to cross-platform converting char* to long long (64-bit)?
How can I convert a char* string to long long (64-bit) integer?
I use MSVC and GCC compilers and my platforms are Windows, Linux and MAC OS.
Thanks.
Amir Saniyan
- 13,014
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2
votes
2 answers
Buggy transfer of single long long numbers to int array
I’m trying to grab a Long Long Int and split each place number into it’s own spot in an array, in order of course, with array[0] being the largest number.
So for instance, if the number was 314, then array[0] = 3, array[1] =1, and array[2] = 4.
This…
ezra_vdj
- 133
- 5
2
votes
3 answers
Pointer conversion to long porting issue in 64 bit env
I'm porting an application from 32 bit to 64 bit.
It is C style coding (legacy product) although it is C++. I have an issue where a combination of union and struct are used to store values. Here a custom datatype called "Any" is used that should…
Reji
- 21
- 1
2
votes
2 answers
Unexpected long long value in C++
In my code I simply scan values of t, n and m respectively. While debugging I found that whatever value I give to m, it is taking the value 0. You can run this code for input :
1
3 4
Here, the output should be 4, but unexpectedly its 0.
On the…
Utkarsh Pandey
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2
votes
3 answers
How to store 64 digits integer in C?
I am dealing with 2 64 digits integers and need to multiple these two numbers.
When I tried to store it into a long long int variable, I got the following compiling error:
1.c: In function ‘main’:
1.c:5:6: warning: integer constant is too large…
Mark Dong
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