ubuntu 14.04 LTS 安装 build-essential 和 libssl-dev 报错
build-essential 和 libssl-dev 安装不上，提示：
build-essential : Depends: g++ (>= 4:4.4.3) but it is not going to be installed
libssl-dev : Depends: libssl1.0.0 (= 1.0.1f-1ubuntu2.15) but 1.0.1f-1ubuntu2.19 is to be installed
Recommends: libssl-doc but it is not going to be installed
详细内容：
~$ sudo apt-get install -y make build-essential libssl-dev zlib1g-dev libbz2-dev libreadline-dev libsqlite3-dev wget curl llvm libncurses5-dev
# 返回内容
Reading package lists... Done
Building dependency tree
Reading state information... Done
make is already the newest version.
make set to manually installed.
curl is already the newest version.
wget is already the newest version.
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
# 报错信息
The following information may help to resolve the situation:
The following packages have unmet dependencies:
build-essential : Depends: g++ (>= 4:4.4.3) but it is not going to be installed
libssl-dev : Depends: libssl1.0.0 (= 1.0.1f-1ubuntu2.15) but 1.0.1f-1ubuntu2.19 is to be installed
Recommends: libssl-doc but it is not going to be installed
E: Unable to correct problems, you have held broken packages.再执行 sudo apt-get install g++，也返回错误：
g++ : Depends: g++-4.8 (>= 4.8.2-5~) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.用的是网易 163 的源 http://mirrors.163.com/
