# [58\. Length of Last Word](https://leetcode.com/problems/length-of-last-word/)

:::spoiler Solution

class Solution {
public:
    int lengthOfLastWord(string s) {
        int n = s.size();
        int res = 0;
        int i = n - 1;
        // 如果遇到空字串，移動指標
        while (i >= 0 && s[i] == ' ') {
            --i;
        }
        // 如果遇到單字，移動指標
        while (i >= 0 && s[i] != ' ') {
            --i;
            ++res;
        }
        // 最後回傳 res
        return res;
    }
};

- T: $O(N)$
- S: $O(1)$
:::