public class HelloWorld{

? ? public static void main(String[] args) {

int age1=24;

int age2=18;

int age3=36;

int age4=27;

? ? ? ? int sum = age1+age2+age3+age4;

? ? ? ? double avg = sum/4;

? ? ? ? int minus = age1-age2;

? ? ? ? int newAge = --age1;

System.out.println("年齡總和："+sum);

? ? System.out.println("平均年齡："+avg);

System.out.println("年齡差值："+minus);

System.out.println("自減后的年齡："+newAge);

}

}