C++ Archives - Page 42 of 68

Difference in make_shared and normal shared_ptr in C++

std::shared_ptr<Object> p1 = std::make_shared<Object>("foo"); std::shared_ptr<Object> p2(new Object("foo")); Many google and stackoverflow posts are there on this, but I am not able to understand ...

May 12, 2022
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Logical XOR operator in C++?

Is there such a thing? It is the first time I encountered a practical need for it, but I don’t see one listed ...

May 12, 2022
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What is a “span” and when should I use one?

Recently I’ve gotten suggestions to use span<T>‘s in my code, or have seen some answers here on the site which use span‘s – ...

May 12, 2022
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How to implement an STL-style iterator and avoid common pitfalls?

I made a collection for which I want to provide an STL-style, random-access iterator. I was searching around for an example implementation of ...

May 12, 2022
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What is the difference between the dot (.) operator and -> in C++? [duplicate]

This question already has answers here: What can I use instead of the arrow operator, `->`? (7 answers) Closed 4 years ago. What ...

May 11, 2022
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int a[] = {1,2,}; Why is a trailing comma in an initializer-list allowed?

Maybe I am not from this planet, but it would seem to me that the following should be a syntax error: int a ...

May 11, 2022
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Easily measure elapsed time

I am trying to use time() to measure various points of my program. What I don’t understand is why the values in the ...

May 11, 2022
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Best way to extract a subvector from a vector?

Suppose I have a std::vector (let’s call it myVec) of size N. What’s the simplest way to construct a new vector consisting of ...

May 11, 2022
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Can a class member function template be virtual?

I have heard that C++ class member function templates can’t be virtual. Is this true? If they can be virtual, what is an ...

May 11, 2022
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How do I check if a C++ std::string starts with a certain string, and convert a substring to an int?

How do I implement the following (Python pseudocode) in C++? if argv[1].startswith('--foo='): foo_value = int(argv[1][len('--foo='):]) (For example, if argv...

May 11, 2022
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