How to get Number pattern in specific shape (java)?

Question

I want to print number pattern like this..

but, I failed to get this triangle shape,and I am confused how to put spaces to get this shape -->

Here's the code i tried so far

public class Ch {

    public static void main(String[] args) {
        int r =Integer.parseInt(args[0]);
        for(int u=1;u<=r;u++)
        { 
            for(int i=u;i>=1;i--)
            {
                System.out.print(i);
            }

            for(int i=2;i<=u;i++)
            {
                System.out.print(i);
            }
            System.out.println();
        }
    }
}

output of this code looks-like this

Thanks

What should happen when there will be let's say 20 lines? I mean what numbers should be displayed for line 10 and greater? — Mateusz Marchel, Sep 14 '17 at 15:04

Malte Hartwig · Answer 1 · 2017-09-14T15:22:58.763

Just add one more step in you main loop before the other two:

for (int i = u; i < r; i++)
{
    System.out.print(" ");
}

This will print spaces to make up for the "missing" numbers.

In regard to Mateusz' comment, look at this answer on how to pad your numbers with spaces to make them equally wide in case you go beyond 9:

static int padding;

public static void main(String[] args)
{
    int r = Integer.parseInt(args[0]);

    padding = Math.max(1, (int) Math.ceil(Math.log10(r)));

    for (int u = 1; u <= r; u++)
    {
        for (int i = u; i < r; i++)
        {
            print(" ");
        }

        for (int i = u; i >= 1; i--)
        {
            print(i);
        }

        for (int i = 2; i <= u; i++)
        {
            print(i);
        }
        System.out.println();
    }
}
private static void print(Object text)
{
    System.out.print(String.format("%1$" + padding + "s", text));
}

score 0 · Answer 2 · answered Sep 14 '17 at 16:28

using 2 for loops

package com.stackoverflow;

import java.util.Scanner;

public class Pyramid {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        System.out.print("Enter the pyramid limit value: ");
        int limit = in.nextInt();
        in.close();
        for (int i = 0; i < limit; i++) {
            for (int j = 0; j < limit + i; j++) {
                if (j < limit -i-1)
                    System.out.print(" ");
                else{               
                    int temp = (limit-j > 0) ? limit-j : j-limit+2;
                    System.out.print(temp);
                }
            }
            System.out.println();
        }
    }

}

using 4 for loops

package com.stackoverflow;

import java.util.Scanner;

public class Pyramid {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        System.out.print("Enter the pyramid limit value: ");
        int limit = in.nextInt();
        in.close();
        for (int i = 0; i < limit; i++) {
            for(int j=0; j<limit-i; j++){
                System.out.print(" ");
            }
            for(int j=0; j<=i; j++){
                System.out.print(i-j+1);
            }
            for(int j=i; j>0; j--){
                System.out.print(i-j+2);
            }
            System.out.println();
        }
    }
}

How to get Number pattern in specific shape (java)?

2 Answers2

using 2 for loops

}

using 4 for loops