作业

public class zuoye2{
public static void main(String[] args){
int sum=0;
int b=1;
for(int a=10;a<=1000;a=a+10){
sum=sum+(a+3)*b;
b=b*-1;
}
System.out.println(sum);
}
}

public class zuoye3{
public static void main(String[] args){
for(int i=1;i<=1000;i++){
if(i%3==0&&i%5==0&&i%7==0)
System.out.println(i);
}
}
}

public class zuoye4{
public static void main(String[] args){
int sum=1,temp=0;
for(int i=1;i<=20;i++){
sum=sum*i;
temp=temp+sum;
}
System.out.println(temp);
}
}

class Address{
String nation;
String province;
String city;
String street;
int postcode;
public void tell(){
System.out.println("国家："+nation+" 省份："+province+" 城市："+city+" 街道："+street+" 邮
编："+postcode);
}
}
public class ClassDemo04{
public static void main(String args[]){
Address add=null;
add=new Address();
add.nation="中国";
add.province="浙江";
add.city="湖州";
add.street="德清";
add.postcode=311212;
add.tell();
}
}