題目：

計算字符串最后一個單詞的長度，單詞以空格隔開。

The java.util.Scanner.hasNext():This method Returns true if this scanner has another token in its input. This method may block while waiting for input to scan. The scanner does not advance past any input

StringcharAt() Method:This method returns the character located at the String's specified index. The indexes start from zero.

java.util.Scanner.Next():This method returns a String object which is a complete token of the Scanner object.

返回Scanner的下一個標記，或指定模式的下一個匹配，即返回的只是第一個輸入

向前跳過當前行，并返回輸入中跳過的輸入行,即返回的是一行

Example:

public class Test {   public static void main(String args[]) {      String s = "Strings are immutable";      char result = s.charAt(8);      System.out.PRintln(result);   }}Result:
a