create linux user with password in one line

#!/bin/bash
# Script to add a user to Linux system
if [ $(id -u) -eq 0 ]; then
    if [ "$#" -eq 2 ]; then
        egrep "^$username" /etc/passwd >/dev/null
        if [ $? -eq 0 ]; then
            echo "$username exists!"
            exit 1
        else
            pass=$(perl -e 'print crypt($ARGV[0], "password")' $password)
            useradd -m -p $pass $username
            [ $? -eq 0 ] && echo "User has been added to system!" || echo "Failed to add a user!"
        fi
    else
    echo "Need two parameters"
    exit 3
    fi
else
    echo "Only root may add a user to the system"
    exit 2
fi