Double pointer letter matching

A daily topic ing, Today is a day easy topic 524. Longest Word in Dictionary through Deleting

class Solution {
    
public:
	static bool cmp(string s1, string s2) {
    
		if (s1.size() == s2.size()) {
    
			return s1 < s2;
		}
		return s1.size() > s2.size();
	}

	string findLongestWord(string s, vector<string>& dictionary) {
    
		sort(dictionary.begin(), dictionary.end(), cmp);
		for (int i = 0; i < dictionary.size(); i++) {
    
			int j = 0, k = 0;
			int len1 = dictionary[i].size(), len2 = s.size();
			while (j < len1 && k < len2) {
    
				if (dictionary[i][j] == s[k]) {
    
					if (j == len1 - 1) {
    
						return dictionary[i];
					}
					j++; k++;
				}
				else {
    
					k++;
				}
			}
		}
		return "";
	}
};