fib.c

#include <inttypes.h>
#include <stdio.h>

#define N 45

static uint32_t
fib (int n)
{
    if (n < 2)
        return 1;

    return fib (n - 2) + fib (n - 1);
}

int
main (void)
{
    for (int i = 0; i < N; i++)
    {
        printf ("fib(%2d) = %" PRIu32 "\n", i, fib (i));
    }

    return 0;
}