Passing by Reference in Range-Based For Loops

Passing by reference in range-based for loops is important for efficiency, especially for large or complex types. The two main benefits of passing by reference are:

• Avoids Copying: Passing by reference avoids copying each element, which can be expensive for large objects.
• Const Safety: Using const ensures that elements are not modified accidentally.

Here's an example:

1#include <vector>
2#include <iostream>
3
4int main() {
5  std::vector<int> Vector{1, 2, 3};
6
7  for (const int& x : Vector) { // Pass by const reference
8    std::cout << x << ", ";
9  }
10}

11, 2, 3,

In this example, const int& x ensures elements are accessed efficiently and safely.