1 /*
2  * Copyright (C) 2011 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 class Main {
18 
19 /*
20     // Iterative version
21     static int fibonacci(int n) {
22         if (n == 0) {
23             return 0;
24         }
25         int x = 1;
26         int y = 1;
27         for (int i = 3; i <= n; i++) {
28             int z = x + y;
29             x = y;
30             y = z;
31         }
32         return y;
33     }
34 */
35 
36    // Recursive version
fibonacci(int n)37    static int fibonacci(int n) {
38         if ((n == 0) || (n == 1)) {
39             return n;
40         } else {
41             return fibonacci(n - 1) + (fibonacci(n - 2));
42         }
43     }
44 
main(String[] args)45     public static void main(String[] args) {
46         String arg = (args.length > 0) ? args[0] : "10";
47         try {
48             int x = Integer.parseInt(arg);
49             int y = fibonacci(x);
50             System.out.printf("fibonacci(%d)=%d\n", x, y);
51             y = fibonacci(x + 1);
52             System.out.printf("fibonacci(%d)=%d\n", x + 1, y);
53         } catch (NumberFormatException ex) {
54             System.err.println(ex);
55             System.exit(1);
56         }
57     }
58 }
59