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         #!/bin/bash
         #the script act on a batch of add user,username at the same password
         read -p "please input username(for example:user1 user2 user3):" -a userall
         len=${#userall[*]}
         for((i=0;i<$len;i++))
         do
         useradd ${userall[i]} -s /sbin/nologin
         echo "${userall[i]}" | passwd --stdin ${userall[i]} &> /dev/null
         pwconv && echo "add succeed :${userall[i]}"
         done
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