如何使不同用户登陆有不同提示符？

下面是我的bashrc文件

# /etc/bashrc

# System wide functions and aliases
# Environment stuff goes in /etc/profile

# by default, we want this to get set.
# Even for non-interactive, non-login shells.
if [ "`id -gn`" = "`id -un`" -a `id -u` -gt 99 ]; then
umask 002
else
umask 022
fi

# are we an interactive shell?
if [ "$PS1" ]; then
case $TERM in
xterm*)
if [ -e /etc/sysconfig/bash-prompt-xterm ]; then
PROMPT_COMMAND=/etc/sysconfig/bash-prompt-xterm
else
PROMPT_COMMAND='echo -ne "\033]0;${USER}@${HOSTNAME%%.*}:${PWD/#$HOME/~}\007"'
fi
;;
screen)
if [ -e /etc/sysconfig/bash-prompt-screen ]; then
PROMPT_COMMAND=/etc/sysconfig/bash-prompt-screen
else
PROMPT_COMMAND='echo -ne "\033_${USER}@${HOSTNAME%%.*}:${PWD/#$HOME/~}\033\\"'
fi
;;
*)
[ -e /etc/sysconfig/bash-prompt-default ] && PROMPT_COMMAND=/etc/sysconfig/bash-prompt-default
;;
esac
# Turn on checkwinsize
shopt -s checkwinsize
[ "$PS1" = "\\s-\\v\\\$ " ] && PS1="\[\e[31m\][\[\e[36m\]\u@\h \w\[\e[31m\]]\[\e[32m\]\\$ \[\e[0m\]"
fi

if ! shopt -q login_shell ; then # We're not a login shell
for i in /etc/profile.d/*.sh; do
if [ -r "$i" ]; then
. $i
fi
done
unset i
fi
# vim:ts=4:sw=4
export G_BROKEN_FILENAMES=1
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/lib/firefox
export XMODIFIERS=@im=SCIM


应该怎样改动才能使不同用户登陆有不同颜色的提示符？
[ "$PS1" = "\\s-\\v\\\$ " ] && PS1="\[\e[31m\][\[\e[36m\]\u@\h \w\[\e[31m\]]\[\e[32m\]\\$ \[\e[0m\]"
是修改给root用户的
想普通用户和root用户的提示颜色不同，应该怎么改？