[剑指Offer][数组]斐波那契数列

1 public class Solution {
2     public int Fibonacci(int n) {
3         if(n == 0 || n == 1) {
4             return n;
5         }
6         return Fibonacci(n-1) + Fibonacci(n-2);
7     }
8 }

 1 public class Solution {
 2     public int Fibonacci(int n) {
 3         int[] array = new int[n + 1];
 4         return Fibonacci(n, array);
 5     }
 6     public int Fibonacci(int n, int[] array) {
 7         if(n == 0 || n == 1) {
 8             return n;
 9         }
10         if(array[n] != 0) {
11             return array[n];
12         }
13         array[n] = Fibonacci(n-1, array) + Fibonacci(n-2, array);
14         return array[n];
15     }
16 }