58. Length of Last Word leetcode solution in c++

 

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

solution:

Runtime: 0 ms, faster than 100.00% of C++ online submissions for Length of Last Word.

Memory Usage: 6.5 MB, less than 51.90% of C++ online submissions for Length of Last Word.

class Solution {
public:
    int lengthOfLastWord(string s) {
        int n=s.length();
        bool flag=false;
        int cnt=0;
        for(int i=n-1;i>=0;i--)
        {
            if(s[i]>=65&&s[i]<=90||s[i]>=97&&s[i]<=122)
            {
                cnt++;
                flag=true;
            }else
            {
                if(flag)
                {
                    break;
                }
            }
        }
        return cnt;
    }
};