题目：

题解：

class Solution {
public:
    int lengthOfLastWord(string s) {
        int index = s.size() - 1;

        while (s[index] == ' ') {
            index--;
        }
        int wordLength = 0;
        while (index >= 0 && s[index] != ' ') {
            wordLength++;
            index--;
        }

        return wordLength;
    }
};