fb

//Fibonacci 
#include <stdio.h>
#include <omp.h>

#define N 40  // Compute Fibonacci(N)

// Sequential Fibonacci (Recursive)
long long fibonacci_sequential(int n) {
    if (n <= 1)
        return n;
    return fibonacci_sequential(n - 1) + fibonacci_sequential(n - 2);
}

// Parallel Fibonacci using OpenMP Tasks
long long fibonacci_parallel(int n) {
    if (n <= 1)
        return n;

    long long x, y;

    #pragma omp task shared(x)
    x = fibonacci_parallel(n - 1);

    #pragma omp task shared(y)
    y = fibonacci_parallel(n - 2);

    #pragma omp taskwait
    return x + y;
}

int main() {
    double start, end;
    long long result_seq, result_par;

    // Sequential Fibonacci
    start = omp_get_wtime();
    result_seq = fibonacci_sequential(N);
    end = omp_get_wtime();
    printf("Sequential Fibonacci(%d) = %lld\n", N, result_seq);
    printf("Sequential Time: %f seconds\n", end - start);

    // Parallel Fibonacci
    start = omp_get_wtime();
    #pragma omp parallel
    {
        #pragma omp single
        result_par = fibonacci_parallel(N);
    }
    end = omp_get_wtime();
    printf("Parallel Fibonacci(%d) = %lld\n", N, result_par);
    printf("Parallel Time: %f seconds\n", end - start);

    return 0;
}