Question

如何循环此WHOLE程序？

public class Experiments {
    public static void main(String[] args) {
        int n;

        System.out.print("Please enter a number:");
        n = TextIO.getlnInt();

        while (n<3) {
            System.out.print("Please enter another number:");
            n = TextIO.getlnInt();
        }
        while (n<=5) {
            System.out.println("Number entered should be more than 5.");
            System.out.println("Please re-enter:");
            n=TextIO.getlnInt();
        }
        if (n%2==0) {
            n=n*2+1;
        }
        else {
            n=n*2;
        }
        System.out.println("The result is "+n +".");
    }
}

打印出结果时：

结果是14。

我想要它说：

有乐趣吗？让我们再做一次。
请输入一个数字：

或

有乐趣吗？想再做一次。按y / n。
请输入一个数字：

Answer 1

你必须做这样的事情：

Scanner s = new Scanner(System.in);
char c;
do {
   your_code
   c = s.next().charAt(0);
} while(c == 'y');

由于这个原因，如果你想继续，当你进入＆＃39; y＆＃39;然后它会再次循环。否则它将退出循环。

Answer 2

将您的代码与wawek中的示例结合使用：

 public class Experiments {
    public static void main(String[] args) {

    Scanner s = new Scanner(System.in);
    do {
       play();
    System.out.println("Again ( press y ) else press Anykey");
       c = s.next().charAt(0);
    } while(c == 'y');

    }

    public static play(){
        int n;

        System.out.print("Please enter a number:");
        n = TextIO.getlnInt();

        while (n<3) {
            System.out.print("Please enter another number:");
            n = TextIO.getlnInt();
        }
        while (n<=5) {
            System.out.println("Number entered should be more than 5.");
            System.out.println("Please re-enter:");
            n=TextIO.getlnInt();
        }
        if (n%2==0) {
            n=n*2+1;
        }
        else {
            n=n*2;
        }
        System.out.println("The result is "+n +".");
    }
    }

Answer 3

public class Experiments {
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
char c;
    int n;
do{
    System.out.print("Please enter a number:");
    n = TextIO.getlnInt();

    while (n<3) {
        System.out.print("Please enter another number:");
        n = TextIO.getlnInt();
    }
    while (n<=5) {
        System.out.println("Number entered should be more than 5.");
        System.out.println("Please re-enter:");
        n=TextIO.getlnInt();
    }
    if (n%2==0) {
        n=n*2+1;
    }
    else {
        n=n*2;
    }
    System.out.println("The result is "+n +".");
    System.out.println("Had fun? press y do it again n to exit");
     c = s.next().charAt(0);
    } while(c == 'y');

}

归功于@wawek

Answer 4

您可以使用递归。样本如下：

public class Experiments {
    public static void main(String[] args) {
        guess();
    }

    public static void guess() {
        int n;

        System.out.print("Please enter a number:");
        n = TextIO.getlnInt();

        while (n<3) {
            System.out.print("Please enter another number:");
            n = TextIO.getlnInt();
        }
        while (n<=5) {
            System.out.println("Number entered should be more than 5.");
            System.out.println("Please re-enter:");
            n=TextIO.getlnInt();
        }
        if (n%2==0) {
            n=n*2+1;
        }
        else {
            n=n*2;
        }
        System.out.println("The result is "+n +".");
        System.out.println("Had fun? Lets do it again.");
        guess();
    }
}

Answer 5

只需读取用户的下一行字符为yes，然后将整个序列作为shwon运行。

public class Experiments {

    public static void main(String[] args) {
        int n;

        while(againFlag=='y'){ 
        System.out.print("Please enter a number:");
        n = TextIO.getlnInt();

        while (n<3) {
            System.out.print("Please enter another number:");
            n = TextIO.getlnInt();
        }
        while (n<=5) {
            System.out.println("Number entered should be more than 5.");
            System.out.println("Please re-enter:");
            n=TextIO.getlnInt();
        }
        if (n%2==0) {
            n=n*2+1;
        }
        else {
            n=n*2;
        }
        System.out.println("The result is "+n +".");
        System.out.println("Had fun. Want do it again?(Press 'y')");
        char againFlag = TextIO.getlnChar();
        }

    }

如何循环这个简单的程序？

5 个答案: