C++ Algorithms and Ranges

#include <algorithm>
#include <iostream>
#include <numeric>
#include <vector>

int main() {
    std::vector<int> v{5, 2, 8, 1, 9, 4};
    std::sort(v.begin(), v.end());
    auto it = std::find(v.begin(), v.end(), 8);
    std::cout << "found 8 at index " << (it - v.begin()) << '\n';
    std::cout << std::accumulate(v.begin(), v.end(), 0) << '\n';
    std::cout << *std::max_element(v.begin(), v.end()) << ' ' << std::count_if(v.begin(), v.end(), [](int n) { return n % 2 == 0; }) << '\n';
    std::vector<int> doubled(v.size());
    std::transform(v.begin(), v.end(), doubled.begin(), [](int n) { return n * 2; });
    for (int n : doubled) std::cout << n << ' ';
    std::cout << '\n';
}

#include <algorithm>
#include <iostream>
#include <ranges>
#include <vector>

int main() {
    std::vector<int> nums{5, 2, 8, 1, 9, 4};
    std::ranges::sort(nums);
    auto evensSquared = nums
        | std::views::filter([](int n) { return n % 2 == 0; })
        | std::views::transform([](int n) { return n * n; });
    for (int n : evensSquared) std::cout << n << ' ';
    std::cout << '\n';
    for (int i : std::views::iota(1, 6) | std::views::reverse) std::cout << i << ' ';
    std::cout << '\n';
}