malloc function - Mini Project: Build & Apply

Using malloc to Allocate Memory in C

📖 Scenario: Imagine you want to store a list of numbers, but you don't know how many numbers you will need to store until the program runs. In C, you can use malloc to ask the computer to give you memory space while the program is running.

🎯 Goal: You will create a program that uses malloc to allocate memory for an array of integers, fill it with values, and then print those values.

📋 What You'll Learn

Create a pointer to an integer array

Use malloc to allocate memory for 5 integers

Assign values to the allocated memory

Print the values stored in the allocated memory

💡 Why This Matters

🌍 Real World

Dynamic memory allocation is useful when you don't know the amount of data in advance, like reading user input or processing files.

💼 Career

Understanding <code>malloc</code> is essential for C programmers working on system software, embedded systems, or performance-critical applications.

1

Create an integer pointer

Declare an integer pointer called numbers.

C

# Declare an integer pointer called numbers
# Your code here

Need a hint?

Use int *numbers; to declare a pointer to integers.

2

Allocate memory for 5 integers

Use malloc to allocate memory for 5 integers and assign it to numbers. Include #include <stdlib.h> at the top.

C

#include 

int *numbers;
# Use malloc to allocate memory for 5 integers and assign to numbers
# Your code here

Need a hint?

Use malloc(5 * sizeof(int)) to allocate memory for 5 integers.

3

Assign values to allocated memory

Use a for loop with variable i from 0 to 4 to assign i * 10 to numbers[i].

C

#include 

int *numbers;
numbers = malloc(5 * sizeof(int));

// Assign values to numbers array
# Your code here

Need a hint?

Use a for loop to assign values like 0, 10, 20, 30, 40 to the array.

4

Print the values and free memory

Use a for loop with variable i from 0 to 4 to print numbers[i] with printf. Then use free(numbers); to release the memory.

C

#include 
#include 

int *numbers;
numbers = malloc(5 * sizeof(int));

for (int i = 0; i < 5; i++) {
    numbers[i] = i * 10;
}

// Print values and free memory
# Your code here

Need a hint?

Use printf("%d\n", numbers[i]); inside a loop to print each number. Don't forget to call free(numbers); after printing.