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原创 Java sort 源码解析 Object part

上次分析了Java对primitive的排序，使用的是优化的快速排序算法。这次介绍Java对Object对象(Comparable)的排序。Java使用了归并对Object排序，关于归并排序的细节，请查看http://zh.wikipedia.org/zh/%E5%BD%92%E5%B9%B6%E6%8E%92%E5%BA%8F归并排序也有一个运行状态图，不过看着确实挺费解的 =。=！

2010-04-23 14:53:00 1179

原创 Java sort 源码解析 primitive part

Java Arrays中提供了对所有类型的排序。其中主要分为primitive和Object两大类，分别使用了快速排序与合并排序。本章以int[] 的排序，讲解Java对primitive排序。首先大家要了解什么是快速排序，它有什么优点，这些我就不累述了，给出地址。http://zh.wikipedia.org/zh/%E5%BF%AB%E9%80%9F%E6%8E%92%E5

2010-04-19 13:14:00 689 2

原创 No9 Java

题目：A Pythagorean triplet is a set of three natural numbers, a b c, for which, a2 + b2 = c2For example, 32 + 42 = 9 + 16 = 25 = 52.Th

2010-04-15 12:28:00 304

原创 No8 Java

题目：Find the greatest product of five consecutive digits in the 1000-digit number.731671765313306249192251196744265747423553491949349698352031277450632623957831801698480186947885184385861

2010-04-15 12:21:00 322

原创 isPrime

用途：判断一个数是否为质数。代码： public static boolean isPrime(int number) { number = number < 0 ? number * (-1) : number; if (number == 1) { return false; }

2010-04-02 11:24:00 934

原创 No7 Java

题目：By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13.What is the 10001st prime number? 翻译：挠齐头陆则质数列撤赖，伺 2，3，5，7，11 高 13。阿

2010-04-02 10:07:00 304

原创 No6 Java

题目：The sum of the squares of the first ten natural numbers is,12 + 22 + ... + 102 = 385The square of the sum of the first ten natural numbers is,(1 + 2 + ... + 10)2

2010-04-02 09:58:00 300

原创 No5 Java

题目：2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder.What is the smallest number that is <dfn title="divisible with no remainder">ev

2010-04-01 14:00:00 324

原创 No4 Java

题目：A palindromic number reads the same both ways. The largest palindrome made from the product of two 2-digit numbers is 9009 = 91 × 99.Find the largest palindrome made from the product of t

2010-04-01 12:46:00 312

原创 No3 Java

题目：The prime factors of 13195 are 5, 7, 13 and 29.What is the largest prime factor of the number 600851475143 ? 翻译：13195 的质数因子是 5，7，13 和 29那600851475143 的最大质数因子是几呢？解题思路：

2010-04-01 12:25:00 335

原创 No2 Java

题目：Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be:1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...Find

2010-03-23 12:16:00 356 2

原创 No1 Java

题目： If we list all the natural numbers below 10 that are multiples of 3or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23. Find the sum of all the multiples of 3 or 5 below 100

2010-02-26 17:57:00 387 1

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