Learn C

What you will practise

Learn C to understand types, arrays and memory. Progress from basic output to functions, pointers and structures.

• Declare variables and choose their types.
• Write functions and traverse arrays.
• Understand addresses and data lifetimes.

Before you start: The course starts with the basics. Read compiler messages carefully as you practise.

A first example to understand

#include <stdio.h>
int main(void) {
    int values[] = {2, 4, 6};
    int total = 0;
    for (int i = 0; i < 3; i++) total += values[i];
    printf("%d\n", total);
    return 0;
}

The array holds three integers. The loop uses indices 0, 1 and 2. The condition i < 3 avoids reading past the last element.

Try it: Replace 6 with 10 and calculate the new total before compiling.

Understand a specific concept

• Understanding Pointers in C (Visual & Practical Guide)