Coding Snippets
Array Stack Basics in JavaScript
Use a JavaScript Array as a Stack
A stack follows LIFO (last in, first out). With arrays, push adds to the top and pop removes from the top.
Use peek to read the top item and isEmpty to check if the stack has elements.
// Array as Stack (LIFO)
const stack = [];
// Push: O(1)
function push(x) {
stack.push(x);
}
// Pop: O(1)
function pop() {
return stack.pop();
}
// Peek: O(1)
function peek() {
return stack[stack.length - 1];
}
// isEmpty: O(1)
function isEmpty() {
return stack.length === 0;
}
// Demo
push(10);
push(20);
push(30);
console.log('Top:', peek()); // 30
console.log('Popping:', pop()); // 30
console.log('Top after pop:', peek()); // 20
// Empty the stack
while (!isEmpty()) {
console.log('Popping:', pop());
}
console.log('Empty?', isEmpty()); // true
Why this matters: Stacks are used in undo systems, depth-first search (DFS), backtracking, and expression evaluation.
#javascript#arrays#stack#beginners#data structures#coding snippet
Coding Snippets
Print Your Name in JavaScript
Learn how to print your own name on the screen using JavaScript. This is one of the first and most fun steps in learning to code!
console.log("Your Name");
#javascript#beginner#print#hello world#coding basics#learn to code#console log
