How do I merge two vectors in C++?

How do I merge two vectors in C++?

You can merge two vectors in C++ using the insert method or the std::copy algorithm. Would you like an example?

Yes, please provide an example using the insert method.

Sure! Here's a simple example:

#include <iostream>
#include <vector>

int main() {
    std::vector<int> vec1 = {1, 2, 3};
    std::vector<int> vec2 = {4, 5, 6};
    vec1.insert(vec1.end(), vec2.begin(), vec2.end());

    for (int i : vec1) {
        std::cout << i << " ";
    }
    return 0;
}

This will merge vec2 into vec1.

What if I want to merge them without modifying the original vectors?

You can create a new vector to hold the merged result. Here's how:

std::vector<int> merged;
merged.reserve(vec1.size() + vec2.size());
merged.insert(merged.end(), vec1.begin(), vec1.end());
merged.insert(merged.end(), vec2.begin(), vec2.end());

This way, vec1 and vec2 remain unchanged.

Thanks! Can I also merge vectors of different types?

No, vectors must contain elements of the same type. However, you can use a std::variant or a std::any to store different types in a single vector.