C++ is C

When C++ was being developed, C compatibility was very important. There are zillions of C programs out there, and the creator of C++ wanted it to be very easy to take a C program and turn it into a C++ program.

Therefore, C++ is just about a superset of C. This means that almost all C programs are C++ programs.

This is a valid C program, and a valid C++ program:

    #include <stdio.h>
    int main() {
        printf("Hello, world!\n");
        return 0;
    }

This is a valid C program, but it is not a valid C++ program, because C++ took over class as a keyword:

    int main() {
        int class=0;
        return class;
    }

Sure, it’s better C++ style to do the first program like this:

    #include <iostream>
    using namespace std;
    int main() {
        cout << "Hello, world!\n";
        return 0;
    }

However, that doesn’t change the fact that the first program is C++.