How do I use iterators in C++ with range-based loops?

How do I use iterators in C++ with range-based loops?

In C++, you can use range-based loops to iterate over containers like vectors and lists. Here's a simple example:

#include <iostream>
#include <vector>

int main() {
    std::vector<int> numbers = {1, 2, 3, 4, 5};
    for (auto num : numbers) {
        std::cout << num << " ";
    }
    return 0;
}

This will print the numbers from 1 to 5.

Can I use range-based loops with custom classes?

Yes, you can! Your custom class needs to implement the begin() and end() methods to return iterators. Here's an example:

class MyCollection {
public:
    std::vector<int> data;
    auto begin() { return data.begin(); }
    auto end() { return data.end(); }
};

MyCollection myCollection;
myCollection.data = {10, 20, 30};
for (auto value : myCollection) {
    std::cout << value << " ";
}

What are the advantages of using range-based loops?

Range-based loops simplify the syntax and reduce the chances of errors, such as off-by-one errors. They also improve code readability.

Are there any performance considerations I should be aware of?

Generally, range-based loops are efficient, but if you're using large containers, consider using references to avoid unnecessary copies. For example:

for (const auto& num : numbers) {
    // Use num without copying
}