#include <iostream>
#include <array>
int main () {
std::array<int, 5> arr;
for (int i = 0; i < 5; i++) arr.at(i) = i + 1;
for (int &n : arr) std::cout << n << ", ";
arr.back() = 99;
std::cout << "\n";
for (int &n : arr) std::cout << n << ", ";
return 0;
}
/*
run:
1, 2, 3, 4, 5,
1, 2, 3, 4, 99,
*/