[ 프로그래머스 ] [1차] 뉴스 클러스터링

문제

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https://school.programmers.co.kr/learn/courses/30/lessons/17677

풀이

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집합의 유사도를 검사하는 자카드 유사도를 구현하는 문제로, 두 문자열의 대소문자를 일치시키고, 각각 비교한다.

#include <string>
#include <unordered_map>

using namespace std;

int solution(string str1, string str2) 
{
    int answer = 0;

    for (int i = 0; i < str1.size(); i++)
    {
        str1[i] = toupper(str1[i]);
    }

    for (int i = 0; i < str2.size(); i++)
    {
        str2[i] = toupper(str2[i]);
    }

    unordered_map<string, int> m_str1, m_str2;
    string s_sum, s_first, s_second;
    int str_cnt = 0;

    for (int i = 0; i < str1.size() - 1; i++)
    {
        s_first = str1[i];
        s_second = str1[i + 1];

        s_sum = s_first + s_second;

        if (str1[i] >= 'A' && str1[i] <= 'Z' && str1[i + 1] >= 'A' && str1[i + 1] <= 'Z')
        {
            if (m_str1.find(s_sum) != m_str1.end())
            {
                m_str1.at(s_sum)++;
            }

            else
            {
                m_str1.insert({ s_sum, 1 });
            }
        }
    }

    for (int i = 0; i < str2.size() - 1; i++)
    {
        s_first = str2[i];
        s_second = str2[i + 1];

        s_sum = s_first + s_second;

        if (str2[i] >= 'A' && str2[i] <= 'Z' && str2[i + 1] >= 'A' && str2[i + 1] <= 'Z')
        {
            if (m_str2.find(s_sum) != m_str2.end())
            {
                m_str2.at(s_sum)++;
            }

            else
            {
                m_str2.insert({ s_sum, 1 });
            }
        }
    }

    int intersect = 0;
    int sum = 0;

    for (auto iter = m_str1.begin(); iter != m_str1.end(); iter++)
    {
        auto find_iter = m_str2.find(iter->first);

        if (find_iter != m_str2.end())
        {
            intersect += min(iter->second, find_iter->second);
            sum += max(iter->second, find_iter->second);
        }

        else
        {
            sum += iter->second;
        }
    }

    for (auto iter = m_str2.begin(); iter != m_str2.end(); iter++)
    {
        auto find_iter = m_str1.find(iter->first);

        if (find_iter == m_str1.end())
        {
            sum += iter->second;
        }
    }

    auto jaccard = 0.0;

    if (sum == 0)
    {
        answer = 65536;
    }

    else
    {
        answer = int (float(intersect) / float(sum) * 65536);
    }

    return answer;
}