#include
using namespace std;
int main()
{
int a[4]={1,2,3};
cout<<2[a]< history 5^C
[root@localhost 20160731]# grep -E --color '^[a-ZA-Z0-9_][email protected]$' file
[root@localhost 20160731]# grep --color '^[a-ZA-Z0-9_][email protected]$' file
[root@localhost 20160731]# grep --color '^[a-ZA-Z0-9_]\[email protected]$' file
IP 3
[root@localhost 20160731]# grep --color '([0-9]{1,3}.){3}[0-9]{1,3}' file
[root@localhost 20160731]# grep --color '^([0-9]{1,3}\.){3}[0-9]{1,3}$' file
[root@localhost 20160731]# grep --color '^\([0-9]\{1,3\}\.\)\{3\}[0-9]\{1,3\}$' file
-E
（） | ｛｝ + ？
【 】
6. 9 10 ， ？（3 -20 ）
3 4 3 4 6 4 3 4 3
（0,0） 2 4 （-1,0） （1,0） （0,2）（0,-2）
【sed】
（ ）
[root@localhost 20160731]# sed '/^c/s/^/\/\//' abc
aaa
bbb
//ccc
ddd
[root@localhost 20160731]# sed '/c$/p' abc
aaa
bbb
ccc
ccc
ddd
[root@localhost 20160731]# cat abc
aaa
bbb
ccc
ddd
[root@localhost 20160731]# sed -n '/c$/p' abc
ccc
[root@localhost 20160731]# sed -n '/^.*\/\//d' abc
[root@localhost 20160731]# cat abc
aaa
bbb
//ccc
ddd
[root@localhost 20160731]# sed -i '/^.*\/\//d' abc abc -i
[root@localhost 20160731]# cat abc
aaa
bbb
ddd
[root@localhost 20160731]# sed -i '/ddd/s/ddd/ccc/g' abc ddd ccc
[root@localhost 20160731]# cat abc
aaa
bbb
ccc
[root@localhost 20160731]#
5 10 5,10 s/^/\/\//
[root@localhost 20160731]# sed '/a\+/s/a/~a~/' abc
//~a~aa
//bbb
//ccc
[root@localhost 20160731]# sed '/a\+/s/a/~a~/g' abc g
//~a~~a~~a~
//bbb
//ccc
[root@localhost 20160731]# sed -n '3p' abc
//ccc
[root@localhost 20160731]# sed -n '1,3p' abc 3 3
//aaa
//bbb
//ccc
[root@localhost 20160731]# sed -n '/aaa/,/ccc/p' abc
//aaa
//bbb
//ccc
[root@localhost 20160731]# sed -n '/aaa/,3p' abc
//aaa
//bbb
//ccc
[root@localhost 20160731]# 3
eg1
，
sed
（1. sed ， ）
（2. ， ）
Gg H h
get hold
n N
[root@localhost 20160731]# cat abc
//aaa
//bbb
//ccc
[root@localhost 20160731]# sed 'G' abc
//aaa
//bbb
//ccc
[root@localhost 20160731]# sed '/b$/G' abc b
//aaa
//bbb
//ccc
[root@localhost 20160731]# tac abc
//ccc
//bbb
//aaa
[root@localhost 20160731]# sed -ne 'H;${x;s/
/ /g;p}' abc ； H hold
//aaa //bbb //ccc
[root@localhost 20160731]# seq 10
1
2
3
4
5
6
7
8
9
10
[root@localhost 20160731]# sed -e '/ddd/H' -e '$G' abc
//aaa
//bbb
//ccc
[root@localhost 20160731]# cat abc
//aaa
//bbb
//ccc
[root@localhost 20160731]# sed -e '/ddd/H' -e '$G' abc
//aaa
//bbb
//ccc
[root@localhost 20160731]# seq 100 | sed -ne 'H;${x;s/
/*/g;s/^*//;p}'
1*2*3*4*5*6*7*8*9*10*11*12*13*14*15*16*17*18*19*20*21*22*23*24*25*26*27*28*29*30*31*32*33*34*35*36*37*38*39*40*41*42*43*44*45*46*47*48*49*50*51*52*53*54*55*56*57*58*59*60*61*62*63*64*65*66*67*68*69*70*71*72*73*74*75*76*77*78*79*80*81*82*83*84*85*86*87*88*89*90*91*92*93*94*95*96*97*98*99*100
[root@localhost 20160731]# seq 100 | sed -ne 'H;${x;s/
/+/g;s/^+//;p}' | bc
5050
[root@localhost 20160731]# sed -n 'n;p' abc
//bbb
[root@localhost 20160731]# sed -n 'p;n' abc 0
//aaa
//ccc
[root@localhost 20160731]# awk '{print $2;}' abc
11
22
33
[root@localhost 20160731]# awk '{print $0;}' abc
//aaa 11
//bbb 22
//ccc 33
[root@localhost 20160731]#