Stack es una estructura de datos lineal que sigue un orden particular en el que se realizan las operaciones. El orden puede ser LIFO (Last In First Out) o FILO (First In Last Out).
Esta estrategia establece que el último elemento que se inserte saldrá primero. Puede tomar una pila de platos colocados uno encima del otro como un ejemplo de la vida real. El plato que ponemos en último lugar está en la parte superior y como quitamos el plato que está en la parte superior, podemos decir que el plato que se puso en último lugar sale primero.
C++
/* C++ program to implement basic stack
operations */
#include <bits/stdc++.h>
using namespace std;
#define MAX 1000
class Stack {
int top;
public:
int a[MAX]; // Maximum size of Stack
Stack() { top = -1; }
bool push(int x);
int pop();
int peek();
bool isEmpty();
};
bool Stack::push(int x)
{
if (top >= (MAX - 1)) {
cout << "Stack Overflow";
return false;
}
else {
a[++top] = x;
cout << x << " pushed into stack\n";
return true;
}
}
int Stack::pop()
{
if (top < 0) {
cout << "Stack Underflow";
return 0;
}
else {
int x = a[top--];
return x;
}
}
int Stack::peek()
{
if (top < 0) {
cout << "Stack is Empty";
return 0;
}
else {
int x = a[top];
return x;
}
}
bool Stack::isEmpty()
{
return (top < 0);
}
// Driver program to test above functions
int main()
{
class Stack s;
s.push(10);
s.push(20);
s.push(30);
cout << s.pop() << " Popped from stack\n";
//print top element of stack after poping
cout << "Top element is : " << s.peek() << endl;
//print all elements in stack :
cout<<"Elements present in stack : ";
while(!s.isEmpty())
{
// print top element in stack
cout<<s.peek()<<" ";
// remove top element in stack
s.pop();
}
return 0;
}
C
// C program for array implementation of stack
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
// A structure to represent a stack
struct Stack {
int top;
unsigned capacity;
int* array;
};
// function to create a stack of given capacity. It initializes size of
// stack as 0
struct Stack* createStack(unsigned capacity)
{
struct Stack* stack = (struct Stack*)malloc(sizeof(struct Stack));
stack->capacity = capacity;
stack->top = -1;
stack->array = (int*)malloc(stack->capacity * sizeof(int));
return stack;
}
// Stack is full when top is equal to the last index
int isFull(struct Stack* stack)
{
return stack->top == stack->capacity - 1;
}
// Stack is empty when top is equal to -1
int isEmpty(struct Stack* stack)
{
return stack->top == -1;
}
// Function to add an item to stack. It increases top by 1
void push(struct Stack* stack, int item)
{
if (isFull(stack))
return;
stack->array[++stack->top] = item;
printf("%d pushed to stack\n", item);
}
// Function to remove an item from stack. It decreases top by 1
int pop(struct Stack* stack)
{
if (isEmpty(stack))
return INT_MIN;
return stack->array[stack->top--];
}
// Function to return the top from stack without removing it
int peek(struct Stack* stack)
{
if (isEmpty(stack))
return INT_MIN;
return stack->array[stack->top];
}
// Driver program to test above functions
int main()
{
struct Stack* stack = createStack(100);
push(stack, 10);
push(stack, 20);
push(stack, 30);
printf("%d popped from stack\n", pop(stack));
return 0;
}
Java
/* Java program to implement basic stack
operations */
class Stack {
static final int MAX = 1000;
int top;
int a[] = new int[MAX]; // Maximum size of Stack
boolean isEmpty()
{
return (top < 0);
}
Stack()
{
top = -1;
}
boolean push(int x)
{
if (top >= (MAX - 1)) {
System.out.println("Stack Overflow");
return false;
}
else {
a[++top] = x;
System.out.println(x + " pushed into stack");
return true;
}
}
int pop()
{
if (top < 0) {
System.out.println("Stack Underflow");
return 0;
}
else {
int x = a[top--];
return x;
}
}
int peek()
{
if (top < 0) {
System.out.println("Stack Underflow");
return 0;
}
else {
int x = a[top];
return x;
}
}
void print(){
for(int i = top;i>-1;i--){
System.out.print(" "+ a[i]);
}
}
}
// Driver code
class Main {
public static void main(String args[])
{
Stack s = new Stack();
s.push(10);
s.push(20);
s.push(30);
System.out.println(s.pop() + " Popped from stack");
System.out.println("Top element is :" + s.peek());
System.out.print("Elements present in stack :");
s.print();
}
}
Python3
# Python program for implementation of stack # import maxsize from sys module # Used to return -infinite when stack is empty from sys import maxsize # Function to create a stack. It initializes size of stack as 0 def createStack(): stack = [] return stack # Stack is empty when stack size is 0 def isEmpty(stack): return len(stack) == 0 # Function to add an item to stack. It increases size by 1 def push(stack, item): stack.append(item) print(item + " pushed to stack ") # Function to remove an item from stack. It decreases size by 1 def pop(stack): if (isEmpty(stack)): return str(-maxsize -1) # return minus infinite return stack.pop() # Function to return the top from stack without removing it def peek(stack): if (isEmpty(stack)): return str(-maxsize -1) # return minus infinite return stack[len(stack) - 1] # Driver program to test above functions stack = createStack() push(stack, str(10)) push(stack, str(20)) push(stack, str(30)) print(pop(stack) + " popped from stack")
C#
// C# program to implement basic stack
// operations
using System;
namespace ImplementStack {
class Stack {
private int[] ele;
private int top;
private int max;
public Stack(int size)
{
ele = new int[size]; // Maximum size of Stack
top = -1;
max = size;
}
public void push(int item)
{
if (top == max - 1) {
Console.WriteLine("Stack Overflow");
return;
}
else {
ele[++top] = item;
}
}
public int pop()
{
if (top == -1) {
Console.WriteLine("Stack is Empty");
return -1;
}
else {
Console.WriteLine("{0} popped from stack ", ele[top]);
return ele[top--];
}
}
public int peek()
{
if (top == -1) {
Console.WriteLine("Stack is Empty");
return -1;
}
else {
Console.WriteLine("{0} popped from stack ", ele[top]);
return ele[top];
}
}
public void printStack()
{
if (top == -1) {
Console.WriteLine("Stack is Empty");
return;
}
else {
for (int i = 0; i <= top; i++) {
Console.WriteLine("{0} pushed into stack", ele[i]);
}
}
}
}
// Driver program to test above functions
class Program {
static void Main()
{
Stack p = new Stack(5);
p.push(10);
p.push(20);
p.push(30);
p.printStack();
p.pop();
}
}
}
Javascript
<script>
/* javascript program to implement basic stack
operations
*/
var t = -1;
var MAX = 1000;
var a = Array(MAX).fill(0); // Maximum size of Stack
function isEmpty() {
return (t < 0);
}
function push(x) {
if (t >= (MAX - 1)) {
document.write("Stack Overflow");
return false;
} else {
t+=1;
a[t] = x;
document.write(x + " pushed into stack<br/>");
return true;
}
}
function pop() {
if (t < 0) {
document.write("Stack Underflow");
return 0;
} else {
var x = a[t];
t-=1;
return x;
}
}
function peek() {
if (t < 0) {
document.write("Stack Underflow");
return 0;
} else {
var x = a[t];
return x;
}
}
function print() {
for (i = t; i > -1; i--) {
document.write(" " + a[i]);
}
}
push(10);
push(20);
push(30);
document.write(pop() + " Popped from stack");
document.write("<br/>Top element is :" + peek());
document.write("<br/>Elements present in stack : ");
print();
// This code is contributed by Rajput-Ji
</script>
C++
// C++ program for linked list implementation of stack
#include <bits/stdc++.h>
using namespace std;
// A structure to represent a stack
class StackNode {
public:
int data;
StackNode* next;
};
StackNode* newNode(int data)
{
StackNode* stackNode = new StackNode();
stackNode->data = data;
stackNode->next = NULL;
return stackNode;
}
int isEmpty(StackNode* root)
{
return !root;
}
void push(StackNode** root, int data)
{
StackNode* stackNode = newNode(data);
stackNode->next = *root;
*root = stackNode;
cout << data << " pushed to stack\n";
}
int pop(StackNode** root)
{
if (isEmpty(*root))
return INT_MIN;
StackNode* temp = *root;
*root = (*root)->next;
int popped = temp->data;
free(temp);
return popped;
}
int peek(StackNode* root)
{
if (isEmpty(root))
return INT_MIN;
return root->data;
}
// Driver code
int main()
{
StackNode* root = NULL;
push(&root, 10);
push(&root, 20);
push(&root, 30);
cout << pop(&root) << " popped from stack\n";
cout << "Top element is " << peek(root) << endl;
cout<<"Elements present in stack : ";
//print all elements in stack :
while(!isEmpty(root))
{
// print top element in stack
cout<<peek(root)<<" ";
// remove top element in stack
pop(&root);
}
return 0;
}
// This is code is contributed by rathbhupendra
C
// C program for linked list implementation of stack
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
// A structure to represent a stack
struct StackNode {
int data;
struct StackNode* next;
};
struct StackNode* newNode(int data)
{
struct StackNode* stackNode =
(struct StackNode*)
malloc(sizeof(struct StackNode));
stackNode->data = data;
stackNode->next = NULL;
return stackNode;
}
int isEmpty(struct StackNode* root)
{
return !root;
}
void push(struct StackNode** root, int data)
{
struct StackNode* stackNode = newNode(data);
stackNode->next = *root;
*root = stackNode;
printf("%d pushed to stack\n", data);
}
int pop(struct StackNode** root)
{
if (isEmpty(*root))
return INT_MIN;
struct StackNode* temp = *root;
*root = (*root)->next;
int popped = temp->data;
free(temp);
return popped;
}
int peek(struct StackNode* root)
{
if (isEmpty(root))
return INT_MIN;
return root->data;
}
int main()
{
struct StackNode* root = NULL;
push(&root, 10);
push(&root, 20);
push(&root, 30);
printf("%d popped from stack\n", pop(&root));
printf("Top element is %d\n", peek(root));
return 0;
}
Java
// Java Code for Linked List Implementation
public class StackAsLinkedList {
StackNode root;
static class StackNode {
int data;
StackNode next;
StackNode(int data) { this.data = data; }
}
public boolean isEmpty()
{
if (root == null) {
return true;
}
else
return false;
}
public void push(int data)
{
StackNode newNode = new StackNode(data);
if (root == null) {
root = newNode;
}
else {
StackNode temp = root;
root = newNode;
newNode.next = temp;
}
System.out.println(data + " pushed to stack");
}
public int pop()
{
int popped = Integer.MIN_VALUE;
if (root == null) {
System.out.println("Stack is Empty");
}
else {
popped = root.data;
root = root.next;
}
return popped;
}
public int peek()
{
if (root == null) {
System.out.println("Stack is empty");
return Integer.MIN_VALUE;
}
else {
return root.data;
}
}
// Driver code
public static void main(String[] args)
{
StackAsLinkedList sll = new StackAsLinkedList();
sll.push(10);
sll.push(20);
sll.push(30);
System.out.println(sll.pop()
+ " popped from stack");
System.out.println("Top element is " + sll.peek());
}
}
Python3
# Python program for linked list implementation of stack
# Class to represent a node
class StackNode:
# Constructor to initialize a node
def __init__(self, data):
self.data = data
self.next = None
class Stack:
# Constructor to initialize the root of linked list
def __init__(self):
self.root = None
def isEmpty(self):
return True if self.root is None else False
def push(self, data):
newNode = StackNode(data)
newNode.next = self.root
self.root = newNode
print ("% d pushed to stack" % (data))
def pop(self):
if (self.isEmpty()):
return float("-inf")
temp = self.root
self.root = self.root.next
popped = temp.data
return popped
def peek(self):
if self.isEmpty():
return float("-inf")
return self.root.data
# Driver code
stack = Stack()
stack.push(10)
stack.push(20)
stack.push(30)
print ("% d popped from stack" % (stack.pop()))
print ("Top element is % d " % (stack.peek()))
# This code is contributed by Nikhil Kumar Singh(nickzuck_007)
C#
// C# Code for Linked List Implementation
using System;
public class StackAsLinkedList {
StackNode root;
public class StackNode {
public int data;
public StackNode next;
public StackNode(int data) { this.data = data; }
}
public bool isEmpty()
{
if (root == null) {
return true;
}
else
return false;
}
public void push(int data)
{
StackNode newNode = new StackNode(data);
if (root == null) {
root = newNode;
}
else {
StackNode temp = root;
root = newNode;
newNode.next = temp;
}
Console.WriteLine(data + " pushed to stack");
}
public int pop()
{
int popped = int.MinValue;
if (root == null) {
Console.WriteLine("Stack is Empty");
}
else {
popped = root.data;
root = root.next;
}
return popped;
}
public int peek()
{
if (root == null) {
Console.WriteLine("Stack is empty");
return int.MinValue;
}
else {
return root.data;
}
}
// Driver code
public static void Main(String[] args)
{
StackAsLinkedList sll = new StackAsLinkedList();
sll.push(10);
sll.push(20);
sll.push(30);
Console.WriteLine(sll.pop() + " popped from stack");
Console.WriteLine("Top element is " + sll.peek());
}
}
/* This code contributed by PrinciRaj1992 */
Javascript
<script>
// javascript Code for Linked List Implementation
var root;
class StackNode {
constructor(data) {
this.data = data;
this.next = null;
}
}
function isEmpty() {
if (root == null) {
return true;
} else
return false;
}
function push(data) {
var newNode = new StackNode(data);
if (root == null) {
root = newNode;
} else {
var temp = root;
root = newNode;
newNode.next = temp;
}
document.write(data + " pushed to stack<br/>");
}
function pop() {
var popped = Number.MIN_VALUE;
if (root == null) {
document.write("Stack is Empty");
} else {
popped = root.data;
root = root.next;
}
return popped;
}
function peek() {
if (root == null) {
document.write("Stack is empty");
return Number.MIN_VALUE;
} else {
return root.data;
}
}
// Driver code
push(10);
push(20);
push(30);
document.write(pop() + " popped from stack<br/>");
document.write("Top element is " + peek());
// This code is contributed by Rajput-Ji
</script>
Publicación traducida automáticamente
Artículo escrito por GeeksforGeeks-1 y traducido por Barcelona Geeks. The original can be accessed here. Licence: CCBY-SA