What are Spread and Rest operators?

// Array spread
const arr1 = [1, 2, 3];
const arr2 = [...arr1, 4, 5]; // [1, 2, 3, 4, 5]

// Clone array
const clone = [...arr1];

// Object spread
const obj1 = { a: 1, b: 2 };
const obj2 = { ...obj1, c: 3 }; // { a: 1, b: 2, c: 3 }

// Merge objects
const merged = { ...obj1, ...obj2 };

// Function arguments
const nums = [1, 2, 3];
Math.max(...nums); // 3

// Function rest parameter
function sum(...numbers) {
  return numbers.reduce((a, b) => a + b, 0);
}
sum(1, 2, 3, 4); // 10

// Destructuring with rest
const [first, ...rest] = [1, 2, 3, 4];
console.log(rest); // [2, 3, 4]

const { a, ...remaining } = { a: 1, b: 2, c: 3 };
console.log(remaining); // { b: 2, c: 3 }