Length of Last Word

Problem Statement - link #

Given a string s consisting of words and spaces, return the length of the last word in the string.

A word is a maximal substring consisting of non-space characters only.

Examples #

Example 1:

Input: s = "Hello World"
Output: 5
Explanation: The last word is "World" with length 5.

Example 2:

Input: s = "   fly me   to   the moon  "
Output: 4
Explanation: The last word is "moon" with length 4.

Example 3:

Input: s = "luffy is still joyboy"
Output: 6
Explanation: The last word is "joyboy" with length 6.

Constraints #

• 1 <= s.length <= 10^4
• s consists of lowercase English letters and ` `.
• There will be at least one word in s.

Solutions #

class Solution {
public:
    int lengthOfLastWord(string s) {
        int res = 0;
        while(s.back() == ' ') s.pop_back();
        for(int i = s.length() - 1; i >= 0 && s[i] != ' '; i--, res++){}
        return res;
    }
};