Vim ships with the syntax highlighting rules for C and C++. This is a curse in disguise, because those rules are extremely old and they only highlight the keywords. This means that any C or C++ source file looks pretty much like plain text, no matter which color scheme you apply.
Vim Syntax Extra is a plugin that fixes this by adding more syntax rules for C and C++. There is a visible difference only in the syntax highlighting once this plugin is installed. Add its Github URL using any of your favorite Vim plugin manager and restart Vim to enjoy it 😊
Tried with: Vim 7.4 and Ubuntu 14.04