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 > 1) ? args[1] : "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.out.println(ex); 55 System.exit(1); 56 } 57 } 58 } 59