Java Help with a pattern using nested loops (java)

  • Thread starter Thread starter MarcL
  • Start date Start date
  • Tags Tags
    Java Loops
AI Thread Summary
The discussion revolves around creating a diamond-shaped pattern in Java using nested loops. The initial code successfully generates the desired pattern for a fixed number of rows but encounters issues when trying to adapt it for user input. The user struggles with managing spaces and the logic for transitioning between the upper and lower triangles of the diamond. Suggestions include simplifying the code by reducing unnecessary loops and clearly defining the desired output structure before coding. The conversation emphasizes the importance of understanding the pattern's requirements for both odd and even row inputs.
MarcL
Messages
170
Reaction score
2
Hey so I have to make a pattern in the shape of a diamond as follow:
Code:
  1
 123
12345
 123
  1

So first, I wrote the code without using a variable n as the number of rows ( from an input from the user) but just the constant i = 5 ( I am sorry for the variable names, I made many patterns and this was just trying to get it to work so I didn't mind it as I was going to change everything later)
Code:
public class PatternChose {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int k = 0, h=2, c=0;
          for (int i=1 ; i<=5 ; i++)
           {
            { for (int u=2 ; u >= i ; u--)
                  System.out.print(" ");
                   h--;
             for (int j=1  ; j<= i + k ; j++)
                System.out.print(j);
             for (int w=2 ; w>= i; w--)
                System.out.print(" ");
               
                }
                k++;
                System.out.println();
                if (h<0)
                    break;}
              for (int i =2 ; i>=1 ; i--){
                 { for (int l=3 ; l>+i ; l--)
                     System.out.print(" ");
                    for (int m= 0 ; m <=i - c ; m++)
                      System.out.print( m + 1);
                 }
                 c++;
                 System.out.println();
                 
              }
    }

}

Then, as this gave the output that I first did up there, I tried to do it with a value inputted by a user:

Code:
import java.util.Scanner;public class PatternChose {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int k = 0, h=2, c=0, row=1;
        Scanner userInput = new Scanner(System.in);
        System.out.println("Please input your value");
          int newUserInput = userInput.nextInt();
          for (int i=1 ; i<=newUserInput ; i++)
           {
            { for (int u=newUserInput - row ; u >= i ; u--)
                  System.out.print(" ");
                   h--;
             for (int j=1  ; j<= i + k ; j++)
                System.out.print(j);
             for (int w=2 ; w>= i; w--)
                System.out.print(" ");
               
                }
                k++;
                System.out.println();
                if (h<0)
                    break;}
              for (int i =2 ; i>=1 ; i--){
                 { for (int l=3 ; l>+i ; l--)
                     System.out.print(" ");
                    for (int m= 0 ; m <=i - c ; m++)
                      System.out.print( m + 1);
                 }
                 c++;
                 row++;
                 System.out.println();
                 
              }
    }

}
But, I'm having an issue while trying to use a value from an input. This is because in my first code, I used the space to the left of the numbers to tell when the program to break to then form a lower triangle. However, I do notice a pattern with the space vs. the number of rows but it doesn't seem like I'd be able to code it as the values always change. ( I don't think I'm making very much sense??)

Any pointers of what I should do?
 
Technology news on Phys.org
Code:
import java.util.Scanner;public class PatternChosen {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int rowsForUpperTriangle = 0,  c=1;
        Scanner userInput = new Scanner(System.in);
        System.out.println("Please input your value");
          int newUserInput = userInput.nextInt();
          int h = newUserInput / 2;
          for (int i=1 ; i<=newUserInput ; i++)
           {
            { for (int u=newUserInput / 2 ; u >= i ; u--)
                  System.out.print(" ");
                   h--;
             for (int j=1  ; j<= i + rowsForUpperTriangle ; j++)
                System.out.print(j);
             for (int SpaceToRight=2 ; SpaceToRight>= i; SpaceToRight--)
                System.out.print(" ");
               
                }
            rowsForUpperTriangle++;
                System.out.println();
                if (h<0)
                    break;}
              for (int i =newUserInput / 2 ; i>=1 ; i--){
                 { for (int l=newUserInput / 2 ; l>=i ; l--)
                     System.out.print(" ");
                    for (int m= 1  ; m <= newUserInput - (2 * c) ; m++)
                      System.out.print( m );
                 }
                 c++;
                 System.out.println();
                 
              }
    }

}

Anyone can tell me how I could reduce this code? I know there are shorter way to code a diamond but this is what I got, which is pretty messy for something so simple I think..
 
MarcL said:
Anyone can tell me how I could reduce this code? I know there are shorter way to code a diamond but this is what I got, which is pretty messy for something so simple I think..

Hmmm... that seems like a lot of extra loops and processing. Before changing your code, maybe write down in words what you are trying to accomplish.

It looks like for an input of 5, your desired output is 5 lines each with 5 characters (either spaces or integers)...how many (outer) loops would you expect to need to write 5 lines one at a time? How many (inner) loops would you expect to need to write 5 characters one at a time?
How do things change for an even input (number of rows) like 4?
 
Thread 'Is this public key encryption?'
I've tried to intuit public key encryption but never quite managed. But this seems to wrap it up in a bow. This seems to be a very elegant way of transmitting a message publicly that only the sender and receiver can decipher. Is this how PKE works? No, it cant be. In the above case, the requester knows the target's "secret" key - because they have his ID, and therefore knows his birthdate.
I tried a web search "the loss of programming ", and found an article saying that all aspects of writing, developing, and testing software programs will one day all be handled through artificial intelligence. One must wonder then, who is responsible. WHO is responsible for any problems, bugs, deficiencies, or whatever malfunctions which the programs make their users endure? Things may work wrong however the "wrong" happens. AI needs to fix the problems for the users. Any way to...
Back
Top