Drill 7: Rewrite it — References and classes

#include <iostream>
#include <string>
#include <vector>

class Course {
public:
    Course(std::string slug, int lessons)
        : slug_(std::move(slug)), lessons_(lessons) {}

    const std::string& slug() const { return slug_; }
    int lessons() const { return lessons_; }

private:
    std::string slug_;
    int lessons_;
};

void print(const Course& course) {
    std::cout << course.slug() << ": " << course.lessons() << " lessons\n";
}