/*
 * Fibonacci numbers
 * F[n] = F[n-1] + F[n-2]
 */

#include <stdio.h>
#include <math.h>

int main(void)
{
    int i;
    float a, b, c;
    b = 1;
    c = 0;
    double phi, psi, phin, psin, delta, r = sqrt(5.), f;

    phi = (1. + r)/2.;
    psi = (1. - r)/2.;
    phin = phi;
    psin = psi;
    delta = 1./(phi - psi);

    for(i = 2; i < 55; i++)
    {
        phin *= phi;
        psin *= psi;
        f = (phin - psin)*delta;
        a = b + c;
        printf("F[%3d] = % 12.0f    % 12.0f\n", i, a, f);
        c = b;
        b = a;
    }

    return 0;
}