JavaScript 배열 메서드: reduce()와 sort() 분석

const arr = [1, 2, 3, 4];
const sum = arr.reduce((acc, value) => acc + value, 0);
console.log(sum); // 10

- `acc`: 누적값(Accumulator)입니다.
- `value`: 현재 순회 중인 배열의 요소입니다.
- `0`: 초기값입니다.

const arr = [1, 2, 3, 4];
const product = arr.reduce((acc, value) => acc * value, 1);
console.log(product); // 24

const items = [
  { name: "Apple", price: 3 },
  { name: "Banana", price: 2 },
  { name: "Orange", price: 4 },
];
const totalPrice = items.reduce((acc, item) => acc + item.price, 0);
console.log(totalPrice); // 9

const nested = [[1, 2], [3, 4], [5]];
const flattened = nested.reduce((acc, value) => acc.concat(value), []);
console.log(flattened); // [1, 2, 3, 4, 5]

const fruits = ["apple", "orange", "banana"];
fruits.sort();
console.log(fruits); // ['apple', 'banana', 'orange']

const numbers = [10, 2, 30, 1];
numbers.sort();
console.log(numbers); // [1, 10, 2, 30] (문자열 기준 정렬)

const numbers = [10, 2, 30, 1];
numbers.sort((a, b) => a - b);
console.log(numbers); // [1, 2, 10, 30]

numbers.sort((a, b) => b - a);
console.log(numbers); // [30, 10, 2, 1]

const words = ["Banana", "apple", "Orange"];
words.sort((a, b) => a.localeCompare(b));
console.log(words); // ['apple', 'Banana', 'Orange']

const people = [
  { name: "Alice", age: 25 },
  { name: "Bob", age: 30 },
  { name: "Charlie", age: 20 },
];
people.sort((a, b) => a.age - b.age);
console.log(people);
// [
// { name: 'Charlie', age: 20 },
// { name: 'Alice', age: 25 },
// { name: 'Bob', age: 30 }
// ]

const original = [3, 1, 4, 2];
const sorted = original.slice().sort((a, b) => a - b);
console.log(original); // [3, 1, 4, 2]
console.log(sorted); // [1, 2, 3, 4]

const original = [3, 1, 4, 2];
const sorted = [...original].sort((a, b) => a - b);
console.log(original); // [3, 1, 4, 2]
console.log(sorted); // [1, 2, 3, 4]