C++ Build Configurations

#include <iostream>
#include <chrono>
#include <vector>
int fibonacci(int n) {
    if (n <= 1) return n;
    return fibonacci(n - 1) + fibonacci(n - 2);
}
int main() {
    auto start = std::chrono::high_resolution_clock::now();
    
    std::vector<int> numbers = {30, 35, 25, 20};
    
    for (int num : numbers) {
        std::cout << "Fibonacci(" << num << ") = " << fibonacci(num) << std::endl;
    }
    
    auto end = std::chrono::high_resolution_clock::now();
    auto duration = std::chrono::duration_cast<std::chrono::milliseconds>(end - start);
    std::cout << "Execution time: " << duration.count() << "ms" << std::endl;
    
    return 0;
}