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Cracking the coding interview--Q5.6

题目原文： Write a program to swap odd and even bits in an integer with as few instructions as possible (e.g., bit 0 and bit 1 are swapped, bit 2 and bit 3 are swapped, etc). 译文：写程序交换一个整数二进制表示中的...

Hawstein | January 4, 2013

Cracking the coding interview--Q5.5

题目原文： Write a function to determine the number of bits required to convert integer A to integer B. Input: 31, 14 Output: 2 译文：写程序计算从整数A变为整数B需要修改的二进制位数。输入：31，14 输出：2 解答这道题目也比较简单，从整数A变...

Hawstein | January 4, 2013

Cracking the coding interview--Q5.4

题目原文： Explain what the following code does: ((n & (n-1)) == 0). 译文：解答以下代码的作用：((n & (n-1)) == 0) 解答这个比较简单，代码的作用是判断一个数是否为2的整数次幂。题目中的判断代码不够严谨，因为当n=0时，上述条件为真，但0并不是2的幂。所以，上述语句可以修改为： 1...

Hawstein | January 4, 2013

Cracking the coding interview--Q5.3

题目原文： Given an integer, print the next smallest and next largest number that have the same number of 1 bits in their binary representation. 译文：给定一个整数x，找出另外两个整数，这两个整数的二进制表示中1的个数和x相同，其中一个是比x大...

Hawstein | January 4, 2013

C/C++字符串处理

前言字符串处理是编程中常遇到的问题，这时候如果能熟练地运用C/C++已有的字符串处理函数，将大大地提高编程效率。 C++ Strings 需要包含头文件<string>，即#include <string>，以下是一些常用函数。 append：在字符串后面追加 1 2 3 4 5 6 7 8 string s1 = "hello ", s2 = ...

Hawstein | January 2, 2013

Cracking the coding interview--Q5.2

题目原文： Given a (decimal - e.g. 3.72) number that is passed in as a string, print the binary representation.If the number can not be represented accurately in binary, print “ERROR”. 译文：给定一个字符...

Hawstein | January 2, 2013

Cracking the coding interview--Q5.1

题目原文： You are given two 32-bit numbers, N and M, and two bit positions, i and j. Write a method to set all bits between i and j in N equal to M (e.g., M becomes a substring of N located at i a...

Hawstein | January 1, 2013

Cracking the coding interview--Q4.8

题目原文： You are given a binary tree in which each node contains a value. Design an algorithm to print all paths which sum up to that value. Note that it can be any path in the tree - it does not...

Hawstein | December 31, 2012

Cracking the coding interview--Q4.7

题目原文： You have two very large binary trees: T1, with millions of nodes, and T2, with hundreds of nodes. Create an algorithm to decide if T2 is a subtree of T1 译文：有两棵很大的二叉树：T1有上百万个结点，T2有上百个结...

Hawstein | December 30, 2012

Cracking the coding interview--Q4.6

题目原文： Design an algorithm and write code to find the first common ancestor of two nodes in a binary tree. Avoid storing additional nodes in a data structure. NOTE: This is not necessarily a bi...

Hawstein | December 29, 2012