题解 | #字符串最后一个单词的长度#

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static int calc(String str){
        str = str.trim();
        int endIndex = str.length()-1;
        while (endIndex >= 0 && str.charAt(endIndex) != ' ') {
            endIndex -- ;
        }
        int startIndex = endIndex + 1;
        String lastword = str.substring(startIndex);    
    return lastword.length();
    }
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
       System.out.print(calc(in.nextLine()));
    }
}