C++ is a direct descendant of the C language; C++ retains almost all of C as a subset and it offers better ways to do things and of course some brand new capabilities.
In addition you don't need to know C in order to learn C++.
EDIT: I never really compare speed between two programming languages (i don't really care much about speed either) but since C++ is newer than C then i'd say C++ is faster? if not then they're probably the same speed, who cares anyways, they're both great for almost anything.
Just about anything that can be done in C can be done the same way in C++. So the two languages are comparable.
Agreed, it depends on what you are writing, as a basic example, this C code is faster: constchar* str= "Hello";
Than this: std::string str = "Hello";
But if you wanted to make "Hello World" with either one of those, C++ would probably be faster because it probably allocated more space than it needed for just "Hello". In C you would have to figure out lengths, allocate manually...
couple of things:
a) @giblit: its just a test to scale it to larger software
b) @op: speed is only comparable if the code is equivalent and even then it can vary from compiler to compiler. i can write assembly code, and there is no guarantee that it is faster than someone writing it in python because mine could be really obtuse while theirs is lean and mean.
AFAIK, there isn't a notable difference in compile time or execution time.
i believe it varies from toolset to toolset. Cubbi would know better though