Count Vowel Substrings of a String

<-E 2062> Count Vowel Substrings of a String

class Solution {
public:
    int countVowelSubstrings(string word) {
        unordered_map<char,int> m;
        int n = word.size();
        int ans = 0;

        for(int i = 0,cnt = 0,j = 0,pref = 0; i < n; i++) {
            if((word[i] == 'a'|| word[i] == 'e'||
                word[i] == 'i'|| word[i] == 'o'||
                word[i] == 'u')) {
                if(m[word[i]]++ == 0)
                     cnt++;

                while(m[word[j]] > 1) {
				    m[word[j++]]--;
                    pref++;
                }

                if(cnt == 5)
                    ans += (1 + pref);
            }
            else {
                   cnt = 0;
                   pref = 0;
                   m.clear();
                   j = i + 1;
               }
        }
        return ans;
    }
};