交互方式批量增加用户

#! /bin/bash
while :
do
        read -p "Please enter prefix & password & num :" pre pass num
        printf "user information
        *********************
        user prefix :   $pre
        user password:  $pass
        user number:    $num
        *********************
"
read -p "Are you sure?[y/n] " action
if [  "$action" == "y"  ];then
        break
fi
done

for i in $( seq  $num )
do
        user=${pre} ${i}
        id $user $> /dev/null
        if [  $? -ne 0  ];then
                useradd $user
                echo "$pass"| passwd -- stdin $user  &>  /dev/null
                if  [  $? -eq 0  ];then
                        echo -e "\033[31m$user\033[Om creat"
                fi
        else
                echo "user $user exist"
        fi
done