tr 那个-c选项什么意思?
没看明白谁给举个例子讲下
HTML code:
Synopsis:
tr [OPTION]... SET1 [SET2]
`tr' copies standard input to standard output, performing one of the
following operations:
* translate, and optionally squeeze repeated characters in the
result,
* squeeze repeated characters,
* delete characters,
* delete characters, then squeeze repeated characters from the
result.
The SET1 and (if given) SET2 arguments define ordered sets of
characters, referred to below as SET1 and SET2. These sets are the
characters of the input that `tr' operates on. The `--complement'
(`-c', `-C') option replaces SET1 with its complement (all of the
characters that are not in SET1).
简单来说, 就是补集的意思
lz可以比较一下
$ echo abccabacca | tr -c ab 0
$ echo abccabacca | tr ab 0
$ echo abccabacca | tr -cs ab 0
相关问答:
#include <stdio.h>
#include <graphics.h>
void main()
{
int x0,y0,x1,y1,driver,mode,i;
driver=VGA;
mode=VGAHI;
initgraph(&driver,&mode,&qu ......
用这本书入门怎么样呢 跟谭浩强的相比如何? 谢谢
我把这本看了几篇,确实很好的书。就不要拿它跟 谭 的书比了, 谭 的书要照顾全国读者。
不可同日而语
一个是国外的,一个是国内的
学完c primer ......
/* Note:Your choice is C IDE
作用: 随机数加密法,,,,
以下有许多不懂,请教一下,请主意代码;
*/
#include <stdio.h>
#include <stdlib.h>
union
{
int value;
struct
{
c ......
ANSI/ISO C 标准这样描述:
在上一个和下一个序列点之间, 一个对象所保存的值至多只能被表
达式的计算修改一次。而且前一个值只能用于决定将要保存的值。
实在不理解这句话,请大家一起说说?? ......
请问各位高手如何用C/C++获得系统未安装补丁
好像很专业的东西。。。
查注册表
每个补丁如果安装了都会在注册表里面登记
请问能不能更清晰些,我想用c\c++查出来,不好意思,我是新手。还望指教。谢
分值 ......