Nested while loops (ksh scripting)


 
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Old 06-15-2010
Error Nested while loops (ksh scripting)

You can use one while inside another?

I made the following script (without really knowing if I can use two while) to get 3 numbers different from each other at random:
Code:
num1=$(( $RANDOM % 10 ))
num2=$num1
while [ $num2 -eq $num1 ]
do
num2=$(( $RANDOM % 10 ))
done
num3=$num1
while [ $num3 -eq $num1 ]
do
while [ $num3 -eq $num2 ]
do
num3=$(( $RANDOM % 10 ))
done
done
echo "$num1 $num2 $num3"

but gave no error but does not work, the script remains open without reacting.
What form should do so to work?

Last edited by fpmurphy; 06-16-2010 at 12:02 AM.. Reason: Added code tags. Translated to english
# 2  
Old 06-16-2010
Quote:
Originally Posted by ale.dle
You can use one while inside another?

I made the following script (without really knowing if I can use two while) to get 3 numbers different from each other at random:
Code:
num1=$(( $RANDOM % 10 ))
num2=$num1
while [ $num2 -eq $num1 ]
do
num2=$(( $RANDOM % 10 ))
done
num3=$num1
while [ $num3 -eq $num1 ]
do
while [ $num3 -eq $num2 ]
do
num3=$(( $RANDOM % 10 ))
done
done
echo "$num1 $num2 $num3"

but gave no error but does not work, the script remains open without reacting.
What form should do so to work?
Code:
while [ $num3 -eq $num2 ]
do
num3=$(( $RANDOM % 10 ))
done


number 3 is not equal to number 2

Last edited by Franklin52; 06-16-2010 at 09:29 AM.. Reason: Please use code tags, thank you!
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