# <span>

**[<span>](https://en.cppreference.com/w/cpp/header/span)** is a non-owning view over a contiguous range of elements (C++20): it holds a pointer and length, allowing you to pass array data without copying. Use it as a function parameter to accept any contiguous container.

It's like a safer `const T*` / `size_t` pair.

## Example

This example passes both vector and C-array data to the same function via span, demonstrating generic array viewing.

```cpp
// compile: g++ -std=c++20 -o spanexample spanexample.cpp
// run: ./spanexample
// description: span as a generic array view

#include <span>
#include <vector>
#include <iostream>

void print_span(std::span<const int> s) {
    for (int x : s) std::cout << x << " ";
    std::cout << "\n";
}

int main() {
    std::vector<int> v = {1, 2, 3, 4, 5};
    print_span(v);
    
    int arr[] = {10, 20, 30};
    print_span(arr);
    
    return 0;
}
```