Table of Contents

1. Introduction
2. Structures
3. Classes
4. Unions
5. Enumerations

2.1 Introduction

• Q/A Format for “A Tour of C++” by Bjarne Stroustrup. [Quizlet Coming Soon] [Anki Coming Soon]

2.2 Structures

• What is a struct in C++?
• How do you access struct members?

void vector_init(Vector& v, int s) {
    v.elem = new double[s]; 
    v.sz = s;
}

• What does the following function do?
• What is the purpose of the new operator in C++?
• ** Difference between . and -> operator in C++?

struct Vector {
    double* elem;
    int sz;
};

void f(Vector v, Vector& rv, Vector* pv) {
    v.sz = 10;    
    rv.sz = 20;  
    pv->sz = 30;  
}

int main() {}

• Is this code valid? What is the output if we cout each sz?
• When defining a struct in C++, the compiler may introduce padding between members. Given a struct like the following: struct Example { char a; int b; char c; };

1. How will the compiler likely arrange the memory layout, and why?
2. How can reordering the members improve memory efficiency?
3. Would making this a class instead of a struct change memory layout?