Rava/examples/20_Benchmark.java

public class Benchmark {
    public static int fibonacci(int n) {
        if (n <= 1) {
            return n;
        }
        return fibonacci(n - 1) + fibonacci(n - 2);
    }

    public static int fibonacciIterative(int n) {
        if (n <= 1) {
            return n;
        }
        int a = 0;
        int b = 1;
        for (int i = 2; i <= n; i++) {
            int temp = a + b;
            a = b;
            b = temp;
        }
        return b;
    }

    public static int countPrimes(int limit) {
        int count = 0;
        for (int n = 2; n <= limit; n++) {
            boolean isPrime = true;
            for (int i = 2; i * i <= n; i++) {
                if (n % i == 0) {
                    isPrime = false;
                    break;
                }
            }
            if (isPrime) {
                count++;
            }
        }
        return count;
    }

    public static long sumLoop(int iterations) {
        long sum = 0L;
        for (int i = 0; i < iterations; i++) {
            sum = sum + i;
        }
        return sum;
    }

    public static int main() {
        System.out.println("=== Rava Benchmark Suite ===");

        long start = System.nanoTime();
        int fib30 = fibonacci(30);
        long end = System.nanoTime();
        long fibTime = (end - start) / 1000000;
        System.out.print("Fibonacci(30) recursive = ");
        System.out.println(fib30);
        System.out.print("Time: ");
        System.out.print(fibTime);
        System.out.println(" ms");

        start = System.nanoTime();
        int fib40iter = fibonacciIterative(40);
        end = System.nanoTime();
        long fibIterTime = (end - start) / 1000000;
        System.out.print("Fibonacci(40) iterative = ");
        System.out.println(fib40iter);
        System.out.print("Time: ");
        System.out.print(fibIterTime);
        System.out.println(" ms");

        start = System.nanoTime();
        int primes = countPrimes(100000);
        end = System.nanoTime();
        long primeTime = (end - start) / 1000000;
        System.out.print("Primes up to 100000 = ");
        System.out.println(primes);
        System.out.print("Time: ");
        System.out.print(primeTime);
        System.out.println(" ms");

        start = System.nanoTime();
        long sumResult = sumLoop(10000000);
        end = System.nanoTime();
        long sumTime = (end - start) / 1000000;
        System.out.print("Sum 0..10000000 = ");
        System.out.println(sumResult);
        System.out.print("Time: ");
        System.out.print(sumTime);
        System.out.println(" ms");

        System.out.println("=== Benchmark Complete ===");
        return 0;
    }
}