How can I use std::vector to store unique elements in C++?

How can I use std::vector to store unique elements in C++?

You can use std::vector along with std::set to ensure uniqueness. First, insert elements into the set, then copy them to the vector.

Can you show me a code example?

Sure! Here's a simple example:

#include <iostream>
#include <vector>
#include <set>

int main() {
    std::set<int> uniqueSet;
    std::vector<int> uniqueVector;

    // Adding elements
    uniqueSet.insert(1);
    uniqueSet.insert(2);
    uniqueSet.insert(1); // Duplicate, won't be added

    // Copying to vector
    uniqueVector.assign(uniqueSet.begin(), uniqueSet.end());

    // Displaying the vector
    for (int num : uniqueVector) {
        std::cout << num << " ";
    }
    return 0;
}

What if I want to maintain the order of insertion?

In that case, you can use std::vector to store elements and check for uniqueness before adding each element. Here's how you can do it.

Thanks! Can you provide that code as well?

Absolutely! Here's an example:

#include <iostream>
#include <vector>
#include <algorithm>

int main() {
    std::vector<int> uniqueVector;
    int newElement;

    while (std::cin >> newElement) {
        if (std::find(uniqueVector.begin(), uniqueVector.end(), newElement) == uniqueVector.end()) {
            uniqueVector.push_back(newElement);
        }
    }

    for (int num : uniqueVector) {
        std::cout << num << " ";
    }
    return 0;
}