如果用户输入特定数字，如何停止我的程序执行下一条语句？

Question

This program prompts the user to enter an odd integer that will decide the height of a specific diamond pattern. My program executes the other statements even though the user inputs one of the other number listed.

if ((number% 2 == 0)|| number <=0 )System.out.println("--- The number you entered is not odd positive!! Please try again!");

 else
    {if (number == 9)

        for (int row = 1 ; row < 10 ; row += 2) {
                    for (int col = 0 ; col < 10 - 1 - row / 2 ; col++)
                        System.out.print(" ");

                    for (int col = 0 ; col < row ; col++)
                        System.out.print("*");
                        System.out.println("");
                }

                for (int row = 7 ; row > 0 ; row -= 2) {
                    for (int col = 0 ; col < 9 - row / 2 ; col++)
                        System.out.print(" ");

                    for (int col = 0 ; col < row ; col++)
                        System.out.print("*");
                        System.out.println(""); }
                        System.out.println("Here is the diamond shape, whose height is " + number);

     //-----------------------------------------------------------------------

       if (number==7)

                for (int row = 1 ; row < 8 ; row += 2) {
                    for (int col = 0 ; col < 8 - 1 - row / 2 ; col++)
                        System.out.print(" ");

                    for (int col = 0 ; col < row ; col++)
                        System.out.print("*");
                        System.out.println("");
                }

                for (int row = 5 ; row > 0 ; row -= 2) {
                    for (int col = 0 ; col < 7 - row / 2 ; col++)
                        System.out.print(" ");

                    for (int col = 0 ; col < row ; col++)
                        System.out.print("*");
                        System.out.println("");}
                        System.out.println("Here is the diamond shape, whose height is " + number);
     //---------------------------------------------------------------------------

       if (number == 5)     

               for (int row = 1 ; row < 6 ; row += 2) {
                    for (int col = 0 ; col < 6 - 1 - row / 2 ; col++)
                        System.out.print(" ");

                    for (int col = 0 ; col < row ; col++)
                        System.out.print("*");
                        System.out.println("");
                }

                for (int row = 3 ; row > 0 ; row -= 2) {
                    for (int col = 0 ; col < 5 - row / 2 ; col++)
                        System.out.print(" ");

                    for (int col = 0 ; col < row ; col++)
                        System.out.print("*");
                        System.out.println("");}
                        System.out.println("Here is the diamond shape, whose height is " + number);
     //--------------------------------------------------------------------------

      if (number == 3)

               for (int row = 1 ; row < 4 ; row += 2) {
                    for (int col = 0 ; col < 4 - 1 - row / 2 ; col++)
                        System.out.print(" ");

                    for (int col = 0 ; col < row ; col++)
                        System.out.print("*");
                        System.out.println("");
                }

                for (int row = 1 ; row > 0 ; row -= 2) {
                    for (int col = 0 ; col < 3 - row / 2 ; col++)
                        System.out.print(" ");

                    for (int col = 0 ; col < row ; col++)
                        System.out.print("*");
                        System.out.println("");}
                        System.out.println("Here is the diamond shape, whose height is " + number);}

Answer 1

Be careful with your coding style. You are not using { after your if conditions, therefore only the next statement is related to the if condition. I suppose the user only can input a single number, therefore you should use else if conditions instead just other if .

It would be better if you post the entire method, instead of just a part of it.

Answer 2

You could add "break;" or "continue;" at the bottom of each option depending on if you want to break out of or continue through the options.

Also consider using a Switch case statement (Code supplied below is untested and just an example).

I don't know if this is suitable for your needs but it seems you have a simple list of numbers which get selected - switches work great for those situations. ie:

pickANumber = sc.nextInt();

        switch (pickANumber) { 
           case 3: 
                for (int row = 1 ; row < 4 ; row += 2) {
                for (int col = 0 ; col < 4 - 1 - row / 2 ; col++)
                    System.out.print(" ");

                for (int col = 0 ; col < row ; col++)
                    System.out.print("*");
                    System.out.println("");
            }

                for (int row = 1 ; row > 0 ; row -= 2) {
                for (int col = 0 ; col < 3 - row / 2 ; col++)
                    System.out.print(" ");

                for (int col = 0 ; col < row ; col++)
                    System.out.print("*");
                    System.out.println("");}
                    System.out.println("Here is the diamond shape, whose height is " + number);}
              break;

           case 5: 
           for (int row = 1 ; row < 6 ; row += 2) {
                for (int col = 0 ; col < 6 - 1 - row / 2 ; col++)
                    System.out.print(" ");

                for (int col = 0 ; col < row ; col++)
                    System.out.print("*");
                    System.out.println("");
            }

            for (int row = 3 ; row > 0 ; row -= 2) {
                for (int col = 0 ; col < 5 - row / 2 ; col++)
                    System.out.print(" ");

                for (int col = 0 ; col < row ; col++)
                    System.out.print("*");
                    System.out.println("");}
                    System.out.println("Here is the diamond shape, whose height is " + number);
              break;

           case 7: 
           for (int row = 1 ; row < 8 ; row += 2) {
                for (int col = 0 ; col < 8 - 1 - row / 2 ; col++)
                    System.out.print(" ");

                for (int col = 0 ; col < row ; col++)
                    System.out.print("*");
                    System.out.println("");
            }

            for (int row = 5 ; row > 0 ; row -= 2) {
                for (int col = 0 ; col < 7 - row / 2 ; col++)
                    System.out.print(" ");

                for (int col = 0 ; col < row ; col++)
                    System.out.print("*");
                    System.out.println("");}
                    System.out.println("Here is the diamond shape, whose height is " + number);
              break;

           case 9:
           for (int row = 1 ; row < 10 ; row += 2) {
                for (int col = 0 ; col < 10 - 1 - row / 2 ; col++)
                    System.out.print(" ");

                for (int col = 0 ; col < row ; col++)
                    System.out.print("*");
                    System.out.println("");
            }

            for (int row = 7 ; row > 0 ; row -= 2) {
                for (int col = 0 ; col < 9 - row / 2 ; col++)
                    System.out.print(" ");

                for (int col = 0 ; col < row ; col++)
                    System.out.print("*");
                    System.out.println(""); }
                    System.out.println("Here is the diamond shape, whose height is " + number);
                break;

             default: System.out.println("Invalid option entered - please try again");