Stacks & Queues

1What is a Stack?✨

A stack is a linear data structure that follows the Last In First Out (LIFO) principle. This means the last item added is the first one to be removed. Think of it as a stack of plates!

2Why Learn Stacks?🎯

• ✓ Useful for function calls and memory management
• ✓ Essential for algorithms like Depth-First Search
• ✓ Helps in undo mechanisms in software applications

3Your First Stack Program💡

Let's implement a simple stack in C:

#include <stdio.h>
#define MAX 10

struct Stack {
    int items[MAX];
    int top;
};

void initStack(struct Stack* s) {
    s->top = -1;
}

int isFull(struct Stack* s) {
    return s->top == MAX - 1;
}

void push(struct Stack* s, int item) {
    if (!isFull(s)) {
        s->items[++(s->top)] = item;
    }
}

4What is a Queue?🚀

A queue is another linear data structure that follows the First In First Out (FIFO) principle. Here, the first item added is the first one to be removed. Imagine a line of people waiting!

5Why Learn Queues?🔍

• ✓ Great for scheduling processes in operating systems
• ✓ Used in breadth-first search algorithms
• ✓ Perfect for handling requests in web servers

6Your First Queue Program⭐

Now, let’s create a simple queue in C:

#include <stdio.h>
#define MAX 10

struct Queue {
    int items[MAX];
    int front, rear;
};

void initQueue(struct Queue* q) {
    q->front = -1;
    q->rear = -1;
}

int isEmpty(struct Queue* q) {
    return q->front == -1;
}

void enqueue(struct Queue* q, int item) {
    if (q->rear < MAX - 1) {
        if (q->front == -1) q->front = 0;
        q->items[++(q->rear)] = item;
    }
}

7What You’ll Build This Grade🧩

• ✓ A mini text editor using stacks for undo/redo functionality
• ✓ A task scheduler using queues for managing tasks
• ✓ A simulation of customer service with both stacks and queues
• ✓ A game that uses stacks for managing game states

Now you're ready to dive into implementing stacks and queues in your projects! Happy coding!