My script does not work properly - linux

Question

Problem: I need to create a file where users and passwords are stored. But my script only saves the password of user1.
Example: I explain myself better with an example. When the two users are created with random password, my script assigns the same password on both users.
user1:Eehei5oo8ohz:/home/user1:/bin/bash
user2:Eehei5oo8ohz:/home/user2:/bin/bash
When the result of my script should be something like this:
user1:Eehei5oo8ohz:/home/user1:/bin/bash
user2:Kln2149sdpja:/home/user2:/bin/bash
My script: This is the script I have used:
#!/bin/bash
##Checking if you are root.##
if [ `id -u` -ne 0 ]
then
echo "you dont are a root user."
exit 1
fi
x=`pwgen 12 1`
for i in {1..2}
do
echo "user$i:#:/home/user$i:/bin/bash" >> users.txt
done
for j in $x
do
sed -i "s/#/$j/" users.txt
done
newusers users.txt
users=`cat users.txt`
login=`echo $i | cut -d: -f1` #username
pass=`cat pass.txt | tr " " _`
password1=`echo $i | cut -d: -f2` #password
for in $users
do
echo "$login:$password1" | chpasswd -m
done
rm users.txt
rm pass.txt
I hope I have explained correctly and appreciate all the help.

Answer 1

You could simplify your script and adapt it as follows (I'm referring to the first part only):
#!/bin/bash
# checking if you are root.##
if [ `id -u` -ne 0 ]
then
echo "you are not the root user!"
exit 1
fi
for i in {1..2}
do
x=`pwgen 12 1`
echo "user$i:$x:/home/user$i:/bin/bash" >> users.txt
done
This will create a file users.txt like the one bellow:
user1:ohng3uxohYi9:/home/user1:/bin/bash
user2:Gah5kiehaemi:/home/user2:/bin/bash
I see no point in creating a file with users and then replacing the # sign with a generated password since you can do that from the start!

Answer 2

You can simplify this script by getting rid of sed editing, eg change:
for i in {1..2}
do
echo "user$i:#:/home/user$i:/bin/bash" >> users.txt
done
for j in $x
do
sed -i "s/#/$j/" users.txt
done
to
pass=`cat pass.txt`
i=1
for pw in $pass
do
echo "user$i:$pw:/home/user$i:/bin/bash" >> users.txt
((i++))
done
This way you can get user numbers and passwords in one go and you are guaranteed to get as many usernames as passwords.