笔试题 求空格分割的英文句子中，最大单词长度。

求空格分割的英文句子中，最大单词长度。例如:"this is a word"，最大单词长度为4。要求:不能用 split 函数对字符串进行切分，算法复杂度为o(n)

public class MaxWordLength {  
  
    public static int maxWordLength(String sentence) {  
        if (sentence == null || sentence.isEmpty()) {  
            return 0;  
        }  
  
        int maxLength = 0;  
        int currentLength = 0;  
  
        for (int i = 0; i < sentence.length(); i++) {  
            char c = sentence.charAt(i);  
  
            if (c == ' ') {  
                // 遇到一个空格，更新最大长度并重置当前长度  
                if (currentLength > maxLength) {  
                    maxLength = currentLength;  
                }  
                currentLength = 0;  
            } else {  
                // 不是空格，增加当前单词的长度  
                currentLength++;  
            }  
  
        return maxLength;  
    }  
  
    public static void main(String[] args) {  
        String sentence = "this is a word";  
        int maxLen = maxWordLength(sentence);  
        System.out.println("Max word length: " + maxLen);  
    }  
}