Is there a better way (performance) calculate fibonacci than this one?

Question

I made this code.. And I need to get the best of it.. I really need the best performance of calculating fibonacci numbers.. please help be..

I\'ve read some code of

Answer 1

Your implementation doesn't work for any decent number because it makes the stack overflow.

I don't see any reason to use recursivity here. Recursivity is pretty but generally heavier (it's language dependent). Here's a working implementation with a simple for loop :

private static BigInteger[] fibTmp = {BigInteger.ZERO, BigInteger.ONE};
private static int maxCached = 1;
public static BigInteger fibonacci(int v) {
    if (fibTmp.length<=v) {
        fibTmp = Arrays.copyOf(fibTmp, v*5/4);
    }
    for (; maxCached

That's a direct implementation without looking for an efficient Fibonacci algorithm in the literature. You'd better look for them.

Note also that this cache based implementation is memory costly and makes only sense if you call the function multiple times.