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App.jsx — InterviewOS Studio
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function App() {
const [todos, setTodos] = React.useState([
{ id: 1, text: 'Learn React Hooks', completed: true },
{ id: 2, text: 'Build with InterviewOS', completed: false },
{ id: 3, text: 'Ace the interview!', completed: false },
])
const [input, setInput] = React.useState('')
 
const addTodo = () => {
if (!input.trim()) return
setTodos(prev => [...prev, {
id: Date.now(), text: input.trim(),
completed: false }])
setInput('')
}
 
const toggleTodo = (id) =>
setTodos(prev => prev.map(t => t.id === id
? { ...t, completed: !t.completed } : t))
 
const deleteTodo = (id) =>
setTodos(prev => prev.filter(t => t.id !== id))
 
const remaining = todos.filter(t => !t.completed).length
const done = todos.filter(t => t.completed).length
 
return (
<div className="todo-shell">
<div className="todo-card">
<div className="todo-header">
<h1>✓ Todo List</h1>
<span className="todo-badge">{done}/{todos.length} done</span>
</div>
<p className="subtitle">remaining + ' tasks remaining'</p>
<div className="progress-track">
<div className="progress-fill" style={{ width: progress + '%' }} />
</div>
<div className="input-row">
<input value={input} onChange={e => setInput(e.target.value)} />
<button onClick={addTodo}>Add</button>
</div>
<div className="todo-list">
{todos.map(todo => (
<div className={'todo-item' + completed}>
<button className={'todo-check' + checked}>
<span className="todo-text">{todo.text}</span>
<button className="del" onClick={() => deleteTodo(todo.id)}>✕</button>
</div>
))}
</div>
</div>
</div>
)
}
Ln 1, Col 1JavaScript JSXInterviewOS Studio
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Clear progression path

Know exactly what to practice next with a structured roadmap from basics to advanced.

Practice-first approach

Learn by doing — every concept is reinforced with hands-on coding exercises.

Handpicked JS questions

Curated JavaScript questions from real frontend interviews at top tech companies.

React deep-dives

Master React concepts, hooks, patterns, and component design questions asked in interviews.

UI coding challenges

Practice building real UI components from scratch — modals, carousels, dropdowns, and more.

Topic-wise structure

Organized modules covering closures, promises, event loop, state management, and beyond.

Understand the 'why'

Every question comes with detailed explanations so you truly understand the concepts.

Real interview patterns

Learn the patterns interviewers look for and how to structure your answers effectively.

Clear progression path

Know exactly what to practice next with a structured roadmap from basics to advanced.

Practice-first approach

Learn by doing — every concept is reinforced with hands-on coding exercises.

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