jewels
를 문자 단위로 분리하여 Set 자료구조에 저장stones
를 순회하며 보석이라면 jewelCount
를 증가시킴jewelCount
반환function numJewelsInStones(jewels: string, stones: string): number {
let jewelCount = 0
const jewelSet = new Set<string>(jewels)
for(const stone of stones) if(jewelSet.has(stone)) jewelCount++
return jewelCount
};