1 Description #
source: https://leetcode.com/problems/length-of-last-word/
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:
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 <= 10^4sconsists of only English letters and spaces' '.- There will be at least one word in
s.
2 Solution #
class Solution {
public:
int lengthOfLastWord(string s) {
// Time complexity: O(N), N is the size of s
// Space complexity: O(1)
// faster than 100.00% of C++
int last_index = s.size() - 1;
while(last_index >= 0 && s[last_index] == ' '){
last_index--;
}
int length = 0;
while(last_index >=0 && s[last_index] != ' '){
length ++;
last_index --;
}
return length;
}
};