What are vectors and how are they used in programming?
This pair (3, 4) is also a mathematical vector. In programming, this name "vector" was originally used to describe any fixed-length sequence of scalar numbers. A vector of length 2 represents …
How is vector implemented in C++ - Stack Overflow
Jan 7, 2020 · Since vector is a template, you actually should have its source to look at if you want a reference – if you can get past the preponderance of underscores, it shouldn't be too hard to …
Slicing a vector in C++ - Stack Overflow
May 27, 2018 · 0 To find a sub vector from index a to b, then, simply do this: vector<int> sub_vec(v.begin() + a, v.begin() + b + 1); This will create a Sub Vector from the a index to the …
When should I use vector::at instead of vector::operator []?
Since it is unlikely that an out of bounds access to a vector is part of the normal program flow (in the case it is, you're right: check beforehand with size instead of letting the exception bubble …
std::vector versus std::array in C++ - Stack Overflow
Dec 12, 2010 · std::vector is a template class that encapsulate a dynamic array 1, stored in the heap, that grows and shrinks automatically if elements are added or removed. It provides all …
c++ - Vector of Vectors to create matrix - Stack Overflow
I am trying to take in an input for the dimensions of a 2D matrix. And then use user input to fill in this matrix. The way I tried doing this is via vectors (vectors of vectors). But I have encount...
Arrays vs Vectors: Introductory Similarities and Differences
Feb 26, 2013 · What are the differences between an array and a vector in C++? An example of the differences might be included libraries, symbolism, abilities, etc. Array Arrays contain a …
Why use a new call with a C++ 'vector'? - Stack Overflow
Feb 13, 2018 · The code vector<someType> myVector; dynamically allocates memory, so any elements stored will live until a delete is called. So how is the following, vector<someType> …
c++ - What's faster, iterating an STL vector with vector::iterator or ...
I have been doing benchmarks myself, and vector.at is much slower than using an iterator, however using vector [i] is much faster than using an iterator. However, you can make the loop …
Iterate through a C++ Vector using a 'for' loop - Stack Overflow
Oct 3, 2012 · I am new to the C++ language. I have been starting to use vectors, and have noticed that in all of the code I see to iterate though a vector via indices, the first parameter of …