# Length Of Last Word Problem

## Description

LeetCode Problem 58.

Given a string s consisting of some words separated by some number of spaces, return the length of the last word in the string.

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

Example 1:

``````1
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Input: s = "Hello World"
Output: 5
Explanation: The last word is "World" with length 5.
``````

Example 2:

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

Example 3:

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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 only English letters and spaces ‘ ‘.
• There will be at least one word in s.

## Sample C++ Code

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class Solution {
public:
/* Start from the tail of s and move backwards to find the first non-space character.
Then from this character, move backwards and count the number of non-space characters
until we pass over the head of s or meet a space character. The count will then be the
length of the last word. */
int lengthOfLastWord(string s) {
int len = 0, tail = s.length() - 1;
while (tail >= 0 && s[tail] == ' ') tail--;
while (tail >= 0 && s[tail] != ' ') {
len++;
tail--;
}
return len;
}
};
``````