[Programmers] Lv 2. 롤케이크 자르기

https://school.programmers.co.kr/learn/courses/30/lessons/132265

프로그래머스

 

function solution(topping) {
    const [lDic, lSizeArr, rDic, rSizeArr] = [new Set(), [], new Set(), []];

    topping.forEach((el, idx) => {
        lDic.add(el);

        if (idx !== 0) rDic.add(topping.at(-idx));

        lSizeArr.push(lDic.size);
        rSizeArr.push(rDic.size);
    });
    return lSizeArr.reduce((acc, el, idx) => (el === rSizeArr.at(-idx - 1)) ? ++acc : acc, 0);
}

GitHub : https://github.com/developeSHG/Algorithm-Baekjoon_Programmers/tree/main/%ED%94%84%EB%A1%9C%EA%B7%B8%EB%9E%98%EB%A8%B8%EC%8A%A4/unrated/132265.%E2%80%85%EB%A1%A4%EC%BC%80%EC%9D%B4%ED%81%AC%E2%80%85%EC%9E%90%EB%A5%B4%EA%B8%B0

GitHub - developeSHG/Algorithm-Baekjoon_Programmers: 백준 and 프로그래머스 소스코드