class Solution {
    public boolean validWordAbbreviation(String word, String abbr) {
        int i = 0, j = 0;
        
        while(i < word.length() && j < abbr.length())
        {
            if(word.charAt(i) == abbr.charAt(j))
            {
                ++i;
                ++j;
                continue;
            }
            
            if (abbr.charAt(j) <= '0' || abbr.charAt(j) > '9') {
                return false;
            }
            
            int start = j;
            while(j < abbr.length() && abbr.charAt(j) >= '0' && abbr.charAt(j) <= '9')
                ++j;
            
            int num = Integer.valueOf(abbr.substring(start,j));
            i += num;
        }
        return i == word.length() && j == abbr.length();
    }
}