斐波那契数列

加个备忘录，不然会重复计算

public class Solution {
    // 0 1 1 2 3 5 8
    int[] dp = new int[45];
    public int Fibonacci(int n) {
        if(n == 0 || n == 1)
            return n;
        if(dp[n] != 0)
            return dp[n];
        return dp[n] = Fibonacci(n-1)+Fibonacci(n-2);
    } 


}