Lists

Linked lists are dynamic structures. That means they can grow or change during program execution.

In this lesson you will learn:

• what a linked list is
• what a node is
• traversal in lists
• search in lists
• insertion in lists

What is a linked list?

It’s a structure formed by nodes.

Each node usually contains:

• a piece of data
• a pointer to the next node

Node in C

struct Node {
    int data;
    struct Node* next;
};

Traversal

Traversing a list means visiting node by node until reaching the end.

current = head;
while (current != NULL) {
    printf("%d\n", current->data);
    current = current->next;
}

Search

Searching in a list implies traversing it until finding the searched value.

while (current != NULL) {
    if (current->data == searched) {
        found = 1;
    }
    current = current->next;
}

Insertion

Insertion can be done at the beginning, at the end, or at an intermediate position.

Insertion at the beginning

new->next = head;
head = new;

Summary

• a linked list is formed by nodes
• it allows traversal, search, and insertion
• it’s more flexible than a fixed-size array

Final idea

The linked list shows a very strong mindset change: you no longer think in fixed positions, but in links between nodes.