0366. Fibonacci

public class Solution {
    /**
     * @param n: an integer
     * @return: an ineger f(n)
     */
    public int fibonacci(int n) {
        if(n==2 || n==3){
            return 1;
        }
        else if(n<=1){
            return 0;
        }
        else{
            return fibonacci(n-1)+fibonacci(n-2);
        }
    }
}

Time Limit Exceeded
90% test cases passed


public class Solution {
    /**
     * @param n: an integer
     * @return: an ineger f(n)
     */
    public int fibonacci(int n) {
        ArrayList<Integer> arr = new ArrayList<>();
        arr.add(0); arr.add(1);
        for(int i=2; i<n; i++){
            arr.add(arr.get(i-1)+arr.get(i-2));
        }
        return arr.get(n-1);
    }
}

100% test cases passedTotal runtime 1522 ms
Your submission beats 71.00% Submissions!