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Questions tagged [uint64]

The uint64 is a datatype that represents an unsigned integer and is coded on 64 bits in memory.

uint64 is a datatype that represents an and is coded on 64 bits in memory. Unlike its counterpart which is , uint64 can only be used to store positive integers, of values between 0 and 264 - 1.

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difference between stdint.h and inttypes.h

What is the difference between stdint.h and inttypes.h? If none of them is used, uint64_t is not recognized but with either of them it is a defined type.
mahmood
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Unexpected uint64 behaviour 0xFFFF'FFFF'FFFF'FFFF - 1 = 0?

Consider the following brief numpy session showcasing uint64 data type import numpy as np a = np.zeros(1,np.uint64) a # array([0], dtype=uint64) a[0] -= 1 a # array([18446744073709551615], dtype=uint64) # this is 0xffff ffff ffff ffff, as…
Albert.Lang
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Macro representing maximum value for uint64_t

I'm seeking for a macro representing the maximum value of uint64_t as UINT_MAX is for unsigned int. i.e. I need this value to guaranteed to be (1<<64)-1. I tried to use UINT64_MAX, but compiling with g++ results in: 'UINT64_MAX' was not declared in…
Subway
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C++ convert string to uint64_t

I am trying to convert from a string to a uint64_t integer. stoi returns a 32 bit integer, so it won't work in my case. Are there other solutions?
Cauchy
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Curious arithmetic error- 255x256x256x256=18446744073692774400

I encountered a strange thing when I was programming under c++. It's about a simple multiplication. Code: unsigned __int64 a1 = 255*256*256*256; unsigned __int64 a2= 255 << 24; // same as the above cerr()<<"a1 is:"<
Hamid Bazargani
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strconv.Itoa64(1234) gives undefined in golang

This is my code: package main import ( "strconv" "fmt" ) func main() { t := strconv.Itoa64(1234) fmt.Println(t) } Problem: Why does it cause the following error message? command-line-arguments .\test.go:7: undefined:…
Yster
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sprintf for unsigned _int64

I am having following code. output of second %d in sprintf is always shown as zero. I think i am specifying wrong specifiers. Can any one help me in getting write string with right values. And this has to achieved in posix standard. Thanks for…
venkysmarty
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How do you deal with numbers larger than UInt64 (C#)

In C#, how can one store and calculate with numbers that significantly exceed UInt64's max value (18,446,744,073,709,551,615)?
Alex
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Convert uint64_t to std::string

How can I transfer uint64_t value to std::string? I need to construct the std::string containing this value For example something like this: void genString(uint64_t val) { std::string str; //.....some code for str str+=(unsigned…
YAKOVM
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UInt64 and "The operation overflows at compile time in checked mode" - CS0220

This feels like a stupid question, but I can't seem to see the answer. I have an UInt64, which is supposed to have a max value of UInt64.MaxValue 18446744073709551615 However, when I try to assign a modest-sized number, I get this overflow error…
Robert Seder
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Is Shifting more than 32 bits of a uint64_t integer on an x86 machine Undefined Behavior?

Learning the hard way, I tried to left shift a long long and uint64_t to more than 32 bits on an x86 machine resulted 0. I vaguely remember to have read somewhere than on a 32 bit machine shift operators only work on the first 32 bits but cannot…
Abhijit
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Convert string to *uint64 in golang

Assume there is a string holding the address of an uint64 type variable, can we parse this address back to an *uint64? For example: i := uint64(23473824) ip := &i str := fmt.Sprintf("%v", ip) u, _ := strconv.ParseUint(str, 0, 64) u is uint64. How…
ecem
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How to define an unsigned 64-bit integer in Delphi7?

In Delphi 7, int64s are signed, if I try to declare a hex constant larger than $8000000000000000 (eg, what is really an uint64) I get an error. Can you advise some workarounds, please?
TheNewbie
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std::atoll with VC++

I have been using std::atoll from cstdlib to convert a string to an int64_t with gcc. That function does not seem to be available on the Windows toolchain (using Visual Studio Express 2010). What is the best alternative? I am also interested in…
Cookie
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Converting (u)int64_t to NSNumbers

So essentially my question is this, I am creating an NSMutableDictionary using uint64_t objects as the key. Is there any better way to create them than doing this? uint64_t bob=7; NSNumber *bobsNumber; #if __LP64__ || TARGET_OS_EMBEDDED ||…
user439407
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