awk reverse string


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# 1  
awk reverse string

Hello,
Can anyone explain for me in this script to reverse the string?
1) the "x=x" part, how it works?
Code:
$ echo welcome | awk '{ for(i=length;i!=0;i--)x=x substr($0,i,1);}END{print x}'
$ emoclew

2) x seems to be an array at the END, but can it automatically print the whole array in awk?
Thanks a lot!
YT
# 2  
"x" is not an array. x=x substr($0,i,1) means that substr($0,i,1) is appended to the variable x; x=x+something.
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# 3  
I see, and I am almost there to catch it.
# 4  
This reverse line by line
Code:
awk '{ for(i=length;i!=0;i--) x=(x substr($0,i,1))}{print x;x=""}'

No need to wait til END for the printing.
I did add parentheses to see what the x does x=(x substr($0,i,1))
It recreate the word by adding one and one letter in reverse order to the x

Value of x by run in loop
Code:
#0 x=""
#1 x=x+"e" x="e"
#2 x=x+"m" x="em"
#3 x=x+"o" x="emo"
etc

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# 5  
If you want to reverse a string, here is the best way:
Code:
$ echo welcome | rev
emoclew

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# 6  
And I see it works fine on multiple lines to Smilie
Code:
echo "toy
home" | rev
yot
emoh

If it cant be done with awk, its not worth doing it Smilie
This User Gave Thanks to Jotne For This Post:
# 7  
Thanks Hanson and Jotne!
I was aware of the rev cmd, but I was trying to catch the awk part. Thanks anyway.
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