Range Loops With and Without References

1#include <iostream>
2 
3int main() {
4    int values[] = {1, 2, 3};
5 
6    for (auto item : values) {
7        item = item * 10;
8    }
9    std::cout << "after copy loop:";
10    for (int v : values) {
11        std::cout << " " << v;
12    }
13    std::cout << "\n";
14 
15    for (auto& item : values) {
16        item = item * 10;
17    }
18    std::cout << "after reference loop:";
19    for (int v : values) {
20        std::cout << " " << v;
21    }
22    std::cout << "\n";
23    return 0;
24}