A basic question of FOR loop


 
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# 1  
A basic question of FOR loop

Hi,
have a basic query.
Please see the below code:

list="one two three"
for var in $list ; do
echo $var
list="nolist"
Done

Wht if I want to print only first/ last line in the list

Eg one & three

Regards
er_ashu
# 2  
awk

don't know if it is the best way but awk will work....

echo $variable | awk '{print $1,$NF}'

note $NF represents the no of fields
# 3  
with zsh and array:

Code:
zsh 4.3.4%zsh 4.3.4% list=(one two three)
zsh 4.3.4% print $list[1]
one
zsh 4.3.4% print $list[-1]
three

otherwise:

Code:
$ list="one two three"
$ printf "${list%% *}\n"
one
$ printf "${list##* }\n"
three

# 4  
with bash
Code:
# var=(one two three)
# echo ${var[0]}
one
# echo ${var[2]}
three

 

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