Meaning of the single quotes in 998'244'353 [duplicate] - c++

This question already has answers here:
Integer literal with single quotes? [duplicate]
(2 answers)
Is there a way to write a large number in C++ source code with spaces to make it more readable? [duplicate]
(6 answers)
Closed 2 years ago.
I recently came across the following C++ code snippet:
int Mod = 998'244'353;
I was intrigued by the use of single quotes in this number.
Could someone elaborate on what this gets interpreted as and why is it accepted?
Also has this formatting always been there in c++?

Related

What does this '::' do in C++? [duplicate]

This question already has answers here:
Using :: (scope resolution operator) in C++
(5 answers)
When do I use a dot, arrow, or double colon to refer to members of a class in C++?
(4 answers)
Closed 2 years ago.
I've started learning Classes in C++ and have come across this :: operator. I have no idea what it means and how/when to use it. It was in every piece of C++ code I'd ever seen. The tutorial I watched didn't explain what it is. Could anyone explain?

C Language hex constant formatting [duplicate]

This question already has answers here:
Is there a way to write a large number in C++ source code with spaces to make it more readable? [duplicate]
(6 answers)
Delimiter tens and units in c++ literals [duplicate]
(2 answers)
Closed 3 years ago.
Many languages allow you to insert underscores into long hex numbers to improve readability. I would like to put underscores into hex numbers that define forty bit hardware addresses. For example I would like to write 0x0400000000 as 0x04_0000_0000.
It is tough for me to count consecutive zeros but I can handle groups of four.
Does C or C++ allow punctuation inside hex constants?
Is there a practical workaround if something like this is not allowed in the language?
Thanks,

What does comma do while using cin in c++ [duplicate]

This question already has answers here:
How does the Comma Operator work
(9 answers)
Closed 4 years ago.
I was practicing practicing some programming and by mistake wrote the following line of code :
int a,b;
cin>>a,b;
Can anybody explain what the comma does here and why doesn't the compiler show any error.
It means that the whole expression has the value b.
But because b is not initialised the behaviour of your code is undefined!
Modern compilers can warm you of this.

In C++, what is "^" symbol means? except XOR [duplicate]

This question already has answers here:
What does the caret (‘^’) mean in C++/CLI?
(8 answers)
Closed 7 years ago.
I read an article about C++ language. There is lines using "^", not XOR.
Sample code is like:
array<String^>^args = System::Environment::GetCommandLineArgs();
The symbol ^ is used for managed pointers.
Read http://msdn.microsoft.com/en-us/library/cxx6f46y.aspx , for more information about them.
They are from C++/CLI though and not C++.

How can an empty for(;;) work? [duplicate]

This question already has answers here:
No loop condition in for and while loop
(5 answers)
Closed 7 years ago.
How does an empty for works?
I have seen this code (and works perfectly)
for(;;) {
And I can't comprehend how is this working or why
It is exactly like while(true).
It skips all the conditions so it just empty-executes since in for the expressions are all optional (i.e. you don't have to provide them if you choose not to).