LeetCode 풀기 - 771. Jewels and Stones

771. Jewels and Stones

 

문제)

You're given strings jewels representing the types of stones that are jewels, and stones representing the stones you have. Each character in stones is a type of stone you have. You want to know how many of the stones you have are also jewels.

Letters are case sensitive, so "a" is considered a different type of stone from "A".

 

 

솔루션1)

class Solution:
    def numJewelsInStones(self, jewels: str, stones: str) -> int:
        # stones를 dict로 구성
        # key = jewel, value = jewel count
        stone_dict = defaultdict(int)
        for stone in stones:
            stone_dict[stone] += 1
        
        jewel_count = 0
        for jewel in jewels:
            jewel_count += stone_dict[jewel]
        return jewel_count

솔루션2)

class Solution:
    def numJewelsInStones(self, jewels: str, stones: str) -> int:
        # stones를 dict로 구성
        # key = jewel, value = jewel count
        stone_dict = defaultdict(int)
        for stone in stones:
            stone_dict[stone] += 1
        
        return sum(stone_dict[jewel] for jewel in jewels)

솔루션3)

• 정의된 문자열에서 해당 문자가 몇 번 존재하는지 count 함수를 사용하는 풀이 방법

class Solution:
    def numJewelsInStones(self, jewels: str, stones: str) -> int:
         return sum(map(stones.count, jewels))