Fibonacci sequence

Fib.java

package com.example.demo;

public class Fib {

    int fib(int n) {
        if (n == 0) return 0;
        if (n == 1) return 1;
        return fib(n - 2) + fib(n - 1);
    }

    int fib(int n, int[] m) {
        if (n == 0) return 0;
        if (n == 1) return 1;
        if (m[n] == 0) {
            m[n] = fib(n - 2, m) + fib(n - 1, m);
        }
        return m[n];
    }

}