Why dynamic memory is needed in C++ - See It in Action

Why dynamic memory is needed

📖 Scenario: Imagine you are creating a program that stores the names of students in a class. Sometimes the class size changes, and you don't know the number of students before running the program.

🎯 Goal: You will learn why dynamic memory is needed by creating a program that stores student names using dynamic memory allocation in C++.

📋 What You'll Learn

Create a pointer to store student names dynamically

Use new to allocate memory for student names

Use a variable to store the number of students

Use a loop to input student names

Print all student names stored in dynamic memory

💡 Why This Matters

🌍 Real World

Dynamic memory is used in programs where the amount of data changes, like storing user input, files, or network data.

💼 Career

Understanding dynamic memory is important for software developers working with C++ to manage resources efficiently and avoid crashes.

1

Create a variable for the number of students

Create an int variable called numStudents and set it to 3.

C++

// Create an int variable called numStudents and set it to 3
// Your code here

Need a hint?

Use int numStudents = 3; to store the number of students.

2

Create a dynamic array for student names

Create a pointer to string called students and use new to allocate an array of numStudents strings.

C++

int numStudents = 3;
// Create a pointer to string called students and allocate memory for numStudents strings
// Your code here

Need a hint?

Use std::string* students = new std::string[numStudents]; to allocate dynamic memory.

3

Input student names using a loop

Use a for loop with variable i from 0 to numStudents - 1 to input student names into students[i].

C++

int numStudents = 3;
std::string* students = new std::string[numStudents];
// Use a for loop to input student names into students array
// Your code here

Need a hint?

Use for (int i = 0; i < numStudents; i++) and std::getline(std::cin, students[i]); to read names.

4

Print student names and free memory

Use a for loop with variable i from 0 to numStudents - 1 to print each student name from students[i]. Then use delete[] students; to free the dynamic memory.

C++

int numStudents = 3;
std::string* students = new std::string[numStudents];
for (int i = 0; i < numStudents; i++) {
    std::cout << "Enter name for student " << i + 1 << ": ";
    std::getline(std::cin, students[i]);
}
// Print all student names and free the dynamic memory
// Your code here

Need a hint?

Use a loop to print names and delete[] students; to free memory.