public class Test1 {
public static void main(String[] args) {
double n1=1;
double n2=1;
double fraction= n1/n2;
double sum=0;
for (int i = 0; i < 20 ; i++) {
double t1 = n1;
double t2 = n2;
n1 = t1+t2;
n2 = t1;
fraction = n1/n2;
sum += fraction;
}
System.out.println(sum);
}
}
public class Test2 {
public static void main(String[] args) {
Scanner reader = new Scanner(System.in);
System.out.print("请输入一串字符串:");
String a = reader.nextLine();
/* char[] arr1= new char[a.length()];
for (int i = 0; i < a.length(); i++) {
arr1[i]=a.charAt(i);
}*/
int n=0;
/** toCharArray() 方法将字符串转换为字符数组。*/
char []arr1 =a.toCharArray();
for (int i = 0; i < a.length()/2; i++) {
if(arr1[i] !=arr1[a.length()-1-i])
{
n++;
}
}
if(n==0){
System.out.println("是回文!");
}
else {
System.out.println("不是回文!");
}
}
}
public class Main {
public static void main(String[] args) {
CollectionBook book1=new CollectionBook("混元功法","马家出版社","666","书库");
CollectionBook book2=new CollectionBook("混元功法","马家出版社","777","书库");
System.out.println(book1.toString());
System.out.println(book2.toString());
System.out.println(book1.equals(book2));
/** (2)通过键盘输入整数,输入0,则对book1进行借阅,
* 输入1,则对book1进行归还操作*/
Scanner reader=new Scanner(System.in);
int a=reader.nextInt();
if(a==0)
{
book1.borrow();
}
if(a==1)
{
book1.revert();
}
}
}
interface Library {
void borrow();
void revert();
}
class Book {
protected String name;
protected String publisher;
public Book(String name, String publisher) {
this.name = name;
this.publisher = publisher;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
Book book = (Book) o;
return Objects.equals(name, book.name) &&
Objects.equals(publisher, book.publisher);
}
@Override
public String toString() {
return "Book{" +
"书名:" + name + '\'' +
", 出版社:" + publisher + '\'' +
'}';
}
}
class CollectionBook extends Book implements Library {
String bNo;
String stacks;
boolean isBorrow;
public CollectionBook(String name, String publisher, String bNo, String stacks) {
super(name, publisher);
this.bNo = bNo;
this.stacks = stacks;
}
@Override
public void borrow() {
if (isBorrow){
System.out.println("对不起,该图书已借阅");
}else {
isBorrow=true;
System.out.println("借阅成功");
}
}
@Override
public void revert() {
if(!isBorrow){
System.out.println("该图书已归还");
}else {
isBorrow=false;
System.out.println("还书成功");
}
}
}