Why pointers are needed in C - See It in Action

Why pointers are needed

📖 Scenario: Imagine you have a box with a toy inside. You want to tell your friend where the toy is without giving the toy itself. You just give the address of the box. This is how pointers work in C.

🎯 Goal: You will create a simple program to show how pointers hold the address of a variable and how changing the value through the pointer changes the original variable.

📋 What You'll Learn

Create an integer variable with a specific value

Create a pointer variable that stores the address of the integer variable

Use the pointer to change the value of the integer variable

Print the original variable before and after changing it through the pointer

💡 Why This Matters

🌍 Real World

Pointers are used in real programs to handle memory directly, work with arrays, and pass large data efficiently.

💼 Career

Understanding pointers is essential for system programming, embedded systems, and performance-critical applications.

1

Create an integer variable

Create an integer variable called number and set it to 10.

C

# Your code here

Need a hint?

Use int to declare the variable and assign 10 to it.

2

Create a pointer to the integer variable

Create a pointer variable called ptr that stores the address of number.

C

int number = 10;
# Your code here

Need a hint?

Use int *ptr to declare a pointer to an integer and assign it the address of number using &.

3

Change the value using the pointer

Use the pointer ptr to change the value of number to 20.

C

int number = 10;
int *ptr = &number;
# Your code here

Need a hint?

Use *ptr to access the value at the address and assign 20 to it.

4

Print the value before and after changing it

Print the value of number before and after changing it through the pointer using printf. First print 10, then after change print 20.

C

#include 

int main() {
    int number = 10;
    int *ptr = &number;

    printf("Before change: %d\n", number);
    *ptr = 20;
    # Your code here
    return 0;
}

Need a hint?

Use printf to show the value of number before and after the change.