809. Expressive Words

https://leetcode.com/problems/expressive-words/description/

class Solution {
public:
    int expressiveWords(string S, vector<string>& words) {
        int res = 0; 
        for (const auto& w : words) {
            if (check(S, w))
                res++;
        }
        return res;
    }
    bool check(const string& s, const string& w) {
        int i = 0, j = 0, m = s.length(), n = w.length();
        while (i < m && j < n) {
            if (s[i] != w[j])   return false;
            int ii = 1, jj = 1;
            while (++i < m && s[i] == s[i-1]) ii++;
            while (++j < n && w[j] == w[j-1]) jj++;
            if (ii < jj || ii < 3 && ii != jj)    return false;
        }
        return i == m && j == n;
    }
};