LC 290. Word Pattern

https://leetcode.com/problems/word-pattern/description/?envType=study-plan-v2&envId=top-interview-150

class Solution {
public:
    bool wordPattern(string pattern, string s) {
        unordered_map<char, string> Map;
        unordered_set<string> mapped;
        int m = pattern.size();
        int n = s.size();
        int idx = 0;
        int pIdx = 0;
        while (idx < n) {
            string str = "";
            while (idx < n && s[idx] != ' ') str.push_back(s[idx++]);
            if (Map.count(pattern[pIdx])) {
                if (Map[pattern[pIdx]] != str) return false;
            } else {
                if (mapped.count(str)) return false;
                mapped.insert(str);
                Map[pattern[pIdx]] = str;
            }
            idx += 1;
            pIdx += 1;
        }
        return pIdx == m;
    }
};

Time Complexity: O(n)
Space: O(m)

拿來做為 map 的基礎題還不錯