function solution(phone_number) { let num = phone_number.length - 4; phone_number.slice(num); for (let i=0; i.push는 배열 메소드! 문자열에 사용할 수 없다.function solution(phone_number) { let hide = phone_number.length - 4; let num = phone_number.slice(hide); let star = "*".repeat(hide); return star + num;}function solution(phone_number) { let hide = phone_number.length - 4; r..
