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EASY

Length of Last Word

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.

Example

Input:

s = "Hello World"

Output:

5

Explanation:
The last word is "World" with length 5.

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Constraints

• 1 ≤ s.length ≤ 10⁴
• s consists of only English letters and spaces ' '.
• There will be at least one word in s.

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Solution: String Traversal

• Time Complexity: O(n)
• Space Complexity: O(1)

C++

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