Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return the length of last word in the string.
If the last word does not exist, return 0.
Note: A word is defined as a character sequence consists of non-space characters only.
For example,
Given s = "Hello World",
return 5.
一刷
题解：
从后向前遍历, 注意忽略尾部空格的方法
Time Complexity - O(n)， Space Complexity - O(1)。
public class Solution {
public int lengthOfLastWord(String s) {
if(s == null || s.length() == 0) return 0;
int count = 0;
for(int i=s.length()-1; i>=0; i--){
if(s.charAt(i)!=' ') count++;
else{
if(count>0) return count;
}
}
return count;
}
}
