What is the easiest way to initialize a std vector with hardcoded elements

I can make an array and initialise it as follows:

int a[] = {10, 20, 30};

How can I make a std::vector and initialise it in the same way?

The best method I know is:

std::vector<int> ints;

ints.push_back(10);
ints.push_back(20);
ints.push_back(30);

Is there an alternative?

Jun 27, 2022 in C++ by Nicholas
• 7,760 points • 592 views

No answer to this question. Be the first to respond.

Your answer

Your name to display (optional):

Email me at this address if my answer is selected or commented on:

Privacy: Your email address will only be used for sending these notifications.

What is the best way to use a HashMap in C++?

The ordered and unordered map containers (std::map and std::unordered map) are included in the standard library. The items in an ordered map are sorted by key, and insert and access are in O (log n). For ordered maps, the standard library often use red black trees. However, this is only an implementation detail. Insert and access are in O in an unordered map (1). It is simply another term for a hashtable. An illustration using (ordered) std::map: #include <map> #include <iostream> #include <cassert> int main(int argc, char ...READ MORE

answered Jun 10, 2022 in C++ by Damon
• 4,960 points • 838 views

0 votes

0 answers

What is the fastest way to transpose a matrix in C++?

I have a reasonably large matrix that I need to transpose. Assume, for example, that my matrix is a b c d e f g h ...READ MORE

Jul 15, 2022 in C++ by Nicholas
• 7,760 points • 687 views

0 votes

0 answers

What is the C++ function to raise a number to a power?

What's the best way to raise a n ...READ MORE

Jun 1, 2022 in C++ by Nicholas
• 7,760 points • 521 views

0 votes

0 answers

How to initialize an std::string with a length?

How can I correctly initialise a string if its length is specified at build time? #include <string> int length = 3; string word[length]; //invalid ...READ MORE

Jul 27, 2022 in C++ by Nicholas
• 7,760 points • 1,212 views

0 votes

0 answers

Efficient way to return a std::vector in c++

When delivering a std::vector in a function, how much data is duplicated, and how much of an optimization will it be to place the std::vector in free-store (on the heap) and provide a pointer instead, i.e. is: std::vector *f() { std::vector *result = new ...READ MORE

Aug 11, 2022 in C++ by Nicholas
• 7,760 points • 577 views

0 votes

1 answer

What is the difference between std::__gcd and std::gcd?

I done some research about this. The ...READ MORE

answered Jun 10, 2022 in C++ by Damon
• 4,960 points • 1,766 views

0 votes

1 answer

How do I erase an element from std::vector<> by index?

You might perform the following to remove a single element: std::vector<int> vec; vec.push_back(6); vec.push_back(-17); vec.push_back(12); // Deletes the second element (vec[1]) vec.erase(std::next(vec.begin())); Alternatively, to remove many elements at once: // ...READ MORE

answered Jun 10, 2022 in C++ by Damon
• 4,960 points • 1,485 views

0 votes

1 answer

How do I reverse a C++ vector?

The algorithm header has a method std::reverse for this purpose. #include <vector> #include <algorithm> int main() { std::vector<int> ...READ MORE

answered Jun 27, 2022 in C++ by Damon
• 4,960 points • 747 views

0 votes

0 answers

Sorting a vector in descending order

Should I utilize std::sort(numbers.begin(), numbers.end(), std::greater<int>()); or std::sort(numbers.rbegin(), numbers.rend()); // ...READ MORE

Jul 5, 2022 in C++ by Nicholas
• 7,760 points • 2,247 views

0 votes

0 answers

Accumulate function in Vector (STL) giving negative sum

I'm receiving a negative total when I run the code below (-294967296). #include<iostream> #include<vector> #include<numeric> using namespace std; int main() { ...READ MORE