1 /* 2 * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 /** 26 * @test 27 * @bug 6959129 28 * @summary COMPARISON WITH INTEGER.MAX_INT DOES NOT WORK CORRECTLY IN THE CLIENT VM. 29 * 30 * @run main/othervm -ea Test6959129 31 */ 32 33 public class Test6959129 { 34 35 public static void main(String[] args) { 36 long start = System.currentTimeMillis(); 37 int min = Integer.MAX_VALUE-30000; 38 int max = Integer.MAX_VALUE; 39 long maxmoves = 0; 40 try { 41 maxmoves = maxMoves(min, max); 42 } catch (AssertionError e) { 43 System.out.println("Passed"); 44 System.exit(95); 45 } 46 System.out.println("maxMove:" + maxmoves); 47 System.out.println("FAILED"); 48 System.exit(97); 49 } 50 /** 51 * Imperative implementation that returns the length hailstone moves 52 * for a given number. 53 */ 54 public static long hailstoneLengthImp(long n) { 55 long moves = 0; 56 while (n != 1) { 57 assert n > 1; 58 if (isEven(n)) { 59 n = n / 2; 60 } else { 61 n = 3 * n + 1; 62 } 63 ++moves; 64 } 65 return moves; 66 } 67 68 private static boolean isEven(long n) { 69 return n % 2 == 0; 70 } 71 72 /** 73 * Returns the maximum length of the hailstone sequence for numbers 74 * between min to max. 75 * 76 * For rec1 - Assume that min is bigger than max. 77 */ 78 public static long maxMoves(int min, int max) { 79 long maxmoves = 0; 80 for (int n = min; n <= max; n++) { 81 if ((n & 1023) == 0) System.out.println(n); 82 long moves = hailstoneLengthImp(n); 83 if (moves > maxmoves) { 84 maxmoves = moves; 85 } 86 } 87 return maxmoves; 88 } 89 } 90