290. Word Pattern

 

https://leetcode.com/problems/word-pattern/

Word Pattern - LeetCode

 

pattern 의 문자열과 str 의 문자열이 pattern 을 이루는지 확인하는 문제

 

올바른 경우

pattern	str	판정
abba	cat dog dog cat	O
aba	cat dog cat	O
aabb	cat cat dog dog	O

 

틀린 경우

pattern	str	판정
abba	dog dog dog dog	X
aaa	cat cat cat cat	X

 

Source

class Solution {
public:
    bool wordPattern(string pattern, string str) {

        stringstream ss(str);
        vector<std::string> vstrings;
        string v;
        while ((ss >> v)) {
            vstrings.push_back(v);
        }

        if (pattern.size() != vstrings.size()) {
		    return false;
	    }
        
        map<char, string> m;
        for (int i = 0; i < pattern.size(); i++) {
            char code = pattern[i];
            if (m.count(code) == false) {
                m[code] = vstrings[i];
            }
            else {
                string cand = m[code];
                if (cand == vstrings[i]) {
                    continue;
                }
                else {
                    return false;
                }
            }
        }

        map<char, string>::iterator it = m.begin();
        string cand = it->second;
        it++;

        while (it != m.end()) {
            if (cand == it->second) {
                return false;
            }
            cand = it->second;
            it++;
        }
        return true;
    }
};