[leetcode]_Longest Common Prefix

public String longestCommonPrefix(String[] strs) {
        
        int len = strs.length;
        if(len == 0) return "";
        
        String commonPrefix = "";

        for(int j = 0; ; j++){ 
            if(j >= strs[0].length()) break;
            int i;
            for(i = 1 ; i < len ; i++){
                if(j >= strs[i].length() || strs[i].charAt(j) != strs[0].charAt(j)) break;
            }
            if(i == len) commonPrefix += strs[0].charAt(j);
            else break;
        }
        
        return commonPrefix;
    }