Counting Lines, Words, and Characters with wc   When working with text files, you sometimes get a large amount of output. Before deciding which approach works best in a specific case, you might want to have an idea about the amount of text you are…

Generating files of any size /dev/zerois a character special device, which infinitely returns the zero byte (\0). The above command will create a file called junk.datathat is exactly 1MB in size. Let's go through the parameters: ifstands for – inputf…

D. Counting Rectangles is Fun time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output There is an n × m rectangular grid, each cell of the grid contains a single integer: zero or one. Let's call t…

sed的正则匹配如何实现非贪婪? sed的正则用的是BREs/EREs,不支持非贪婪模式.当然有一些方法可以实现非贪婪,比如: $ echo abcOabcdOabc | sed 's/.*O//' 结果是abc: $ echo abcOabcdOabc | sed 's/[^O]*O//' 结果是abcdOacb,变相实现了非贪婪的匹配. 但如果是这种情况: <div>...</div>blabla<div>...</div> 如果想用sed去除前后的&l…

本文中的提到GNU扩展时,表示该功能是GNU为sed提供的(即GNU版本的sed才有该功能),一般此时都会说明:如果要写具有可移植性的脚本,应尽量避免在脚本中使用该选项. 本文中的正则表达式几乎和grep中支持的一样.但还是有少数几个是sed自身才能解析的表达式.因此本译文中只对这些sed自身才支持的正则表达式做翻译,其余sed支持的通用性正则表达式见grep命令中文手册. 此外,除了正则表达式部分,还有些地方没有进行翻译,因为个人觉得几乎用不上,没必要翻译.但为了保持文章的完整性,仍给出了原文…

sed系列文章: sed修炼系列(一):花拳绣腿之入门篇sed修炼系列(二):武功心法(info sed翻译+注解)sed修炼系列(三):sed高级应用之实现窗口滑动技术sed修炼系列(四):sed中的疑难杂症 本文中提到GNU扩展时,表示该功能是GNU为sed提供的(即GNU版本的sed才有该功能),一般此时都会说明:如果要写具有可移植性的脚本,应尽量避免在脚本中使用该选项. 本文中的正则表达式几乎和grep中支持的一样.但还是有少数几个是sed自身才能解析的表达式.因此本译文中只对这些sed…

Notes from The C Programming Language A decimal point in a constant indicates that it is floating point, however, so $5.0/9.0$ i not truncated because it is the ratio of two floating-point values. printf specification %3.0f says that a floating-point…

E. Zbazi in Zeydabad time limit per test 5 seconds memory limit per test 512 megabytes input standard input output standard output A tourist wants to visit country Zeydabad for Zbazi (a local game in Zeydabad). The country Zeydabad is a rectangular t…

Oil Deposits Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 20058    Accepted Submission(s): 11521 Problem Description The GeoSurvComp geologic survey company is responsible for detecting under…

                                                               1334: Oil Deposits 时间限制(普通/Java):1000MS/10000MS     内存限制:65536KByte总提交: 555            测试通过:404 描述 The GeoSurvComp geologic survey company is responsible for detecting underground oil dep…