stl Archives - Page 5 of 6

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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Sorting a vector in descending order

Should I use std::sort(numbers.begin(), numbers.end(), std::greater<int>()); or std::sort(numbers.rbegin(), numbers.rend()); // note: reverse iterators to sort a vector in descending order? Are there any ...

May 11, 2022
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Why does the C++ STL not provide any “tree” containers?

Why does the C++ STL not provide any “tree” containers, and what’s the best thing to use instead? I want to store a ...

May 7, 2022
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Why can’t I make a vector of references?

When I do this: std::vector<int> hello; Everything works great. However, when I make it a vector of references instead: std::vector<int &> hello; I ...

May 7, 2022
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How to check that an element is in a std::set?

How do you check that an element is in a set? Is there a simpler equivalent of the following code: myset.find(x) != myset.end() ...

May 7, 2022
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What’s the difference between “STL” and “C++ Standard Library”?

Someone brought this article to my attention that claims (I’m paraphrasing) the STL term is misused to refer to the entire C++ Standard ...

May 4, 2022
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Iteration over std::vector: unsigned vs signed index variable

What is the correct way of iterating over a vector in C++? Consider these two code fragments, this one works fine: for (unsigned ...

May 4, 2022
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Initializing a static std::map in C++

What is the right way of initializing a static map? Do we need a static function that will initialize it? 12 s 12 ...

May 3, 2022
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How to find if a given key exists in a C++ std::map

I’m trying to check if a given key is in a map and somewhat can’t do it: typedef map<string,string>::iterator mi; map<string, string> m; ...

May 1, 2022
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How do I erase an element from std::vector by index?

I have a std::vector<int>, and I want to delete the n’th element. How do I do that? std::vector<int> vec; vec.push_back(6); vec.push_back(-17); vec.push_back(12); vec.erase(???); ...

April 29, 2022
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