C++ Structured VS. Functional Programming

functional.cpp

#include <iostream>
#include <ranges>
#include <cmath>

int main() {
    int p, q;
    std::cin >> p;
    std::cin >> q;
    for (const auto &r :
            std::views::iota(p, q)
            | std::views::filter([](int n) {
                return (n > 1) && (n == 2 || (n % 2 && std::ranges::empty(
                    std::views::iota(2, static_cast<int>(std::sqrt(n)) + 1)
                    | std::views::filter([n](int i) { return n % i == 0; })))); }))
        std::cout << r << ' ';
    std::cout << std::endl;
}

structured.cpp

#include <iostream>
#include <cmath>

bool isPrime(int n) {
    if (n < 2) return false;
    if (n == 2) return true;
    if (n % 2 == 0) return false;
    for (int i = 2; i <= std::sqrt(n); i++) {
        if (n % i == 0) return false;
    }
    return true;
}

void printPrimesInRange(int p, int q) {
    for (int n = p; n < q; ++n) {
        if (isPrime(n)) {
            std::cout << n << ' ';
        }
    }
    std::cout << std::endl;
}

int main() {
    int p, q;
    std::cin >> p;
    std::cin >> q;
    printPrimesInRange(p, q);
}