#include <iostream>
#include <optional>
#include <vector>

std::optional<int> first_feasible(const std::vector<int>& durations, int limit) {
    for (int value : durations) { if (value >= 0 && value <= limit) { return value; } }
    return std::nullopt;
}

int main() {
    std::vector<int> durations{75, 42, 55};
    auto result = first_feasible(durations, 60);
    if (result) { std::cout << "Feasible: " << *result << " minutes\n"; }
    std::cout << "Missing fallback: " << first_feasible(durations, 20).value_or(-1) << '\n';
}