How to implement dynamic expansion of queues and stacks in C language
Queues and stacks are commonly used data structures in C language. They can help us process data efficiently. However, in actual programming, we often encounter situations where the amount of data exceeds the capacity limit. At this time, we need to implement dynamic expansion of queues and stacks to meet actual needs.
6How to implement dynamic expansion of queues and stacks in C language
Dynamic expansion means that when the capacity of the data structure is insufficient, the capacity is automatically expanded according to the actual situation to accommodate more elements. Below, we will introduce how to implement dynamic expansion of queues and stacks in C language respectively.
First, let's look at the dynamic expansion of the queue. A queue is a first-in-first-out (FIFO) data structure. In C language, we can use arrays to implement queues. In order to achieve dynamic expansion, we can define an initial capacity and continue to increase the capacity as elements are inserted.
The specific implementation is as follows:
typedef struct {
int *data;
int front;
int rear;
int capacity;
} Queue;
void enqueue(Queue *queue, int value) {
if (queue->rear == queue->capacity) {
//The queue is full and needs to be expanded
queue->capacity *= 2;
queue->data = realloc(queue->data, sizeof(int) * queue->capacity);
}
queue->data[queue->rear++] = value;
}
int dequeue(Queue *queue) {
if (queue->front == queue->rear) {
//The queue is empty, throw an exception or return a specific value
}
return queue->data[queue->front++];
}
In the above code, we define a Queue structure, which contains an array data pointing to an int type, a front representing the head of the queue, a rear representing the tail of the queue, and a capacity.
In the enqueue function, we first determine whether the queue is full. If it is full, double the capacity and use the realloc function to reallocate the memory space. Then, insert the new element at the end of the queue.
In the dequeue function, we first determine whether the queue is empty. If it is empty, we can throw an exception or return a specific value. Then, return the element at the head of the queue and move the front pointer one position back.
Next, let's look at the dynamic expansion of the stack. The stack is a last-in-first-out (LIFO) data structure. In C language, we can also use arrays to implement stacks. In order to achieve dynamic expansion, we can define an initial capacity and continuously increase the capacity as elements are pushed onto the stack.
The specific implementation is as follows:
typedef struct {
int *data;
int top;
int capacity;
} Stack;
void push(Stack *stack, int value) {
if (stack->top == stack->capacity) {
// The stack is full and needs to be expanded
stack->capacity *= 2;
stack->data = realloc(stack->data, sizeof(int) * stack->capacity);
}
stack->data[stack->top++] = value;
}
int pop(Stack *stack) {
if (stack->top == 0) {
// The stack is empty, throw an exception or return a specific value
}
return stack->data[–stack->top];
}
In the above code, we define a Stack structure, which contains an array data pointing to an int type, a top representing the top of the stack, and a capacity.
In the push function, we first determine whether the stack is full. If it is full, double the capacity and use the realloc function to reallocate the memory space. Then, push the new element onto the stack.
In the pop function, we first determine whether the stack is empty. If it is empty, we can throw an exception or return a specific value. Then, return the element at the top of the stack and move the top pointer forward by one.
Through the above code, we can implement dynamic expansion of queues and stacks in C language. In this way, we can no longer be limited by fixed capacity when processing large amounts of data, improving the efficiency and flexibility of the program.
To sum up, the key to realizing dynamic expansion of queues and stacks is to determine whether the capacity is full when inserting elements, and if so, perform the expansion operation. By properly designing data structures and algorithms, we can better utilize the features of the C language and improve program performance and scalability. I hope this article will help you achieve dynamic expansion in C language programming!
Part of the code is transferred from: https://www.songxinke.com/c/2023-08/255003.html