在主方法中创建String型变量，并判断变量的前导和后置字符串

public class Startsorends {    public static void main(String args[]){        String str1 = "aa22bbcc";        String str2 = "bb22ccdd";        boolean b1 = str1.startsWith("aa");        boolean b2 = str1.endsWith("cc");        boolean b3 = str2.startsWith("aa");        boolean b4 = str2.endsWith("cc");        System.out.println(b1);        System.out.println(b2);        System.out.println(b3);        System.out.println(b4);    }}