Java Program to Print Left Pascals Number Triangle

Write a Java program to print the left pascal number triangle using for loop.

import java.util.Scanner;

public class LeftPascalNumber1 {
	
	private static Scanner sc;
	
	public static void main(String[] args) {
		sc = new Scanner(System.in);
		
		int i, j, k;
		
		System.out.print("Enter Left Pascals Number Triangle Pattern Rows = ");
		int rows = sc.nextInt();
		
		System.out.println("Printing Left Pascals Triangle Number Pattern");
		
		for (i = 1 ; i <= rows; i++ ) 
		{
			for (j = i ; j < rows; j++ ) 
			{
				System.out.print("  ");
			}
			for(k = 1; k <= i; k++) 
			{
				System.out.print(k + " ");
			}
			System.out.println();
		}
		
		for (i = rows; i >= 1; i-- ) 
		{
			for (j = i ; j <= rows; j++ ) 
			{
				System.out.print("  ");
			}
			for(k = 1; k < i; k++) 
			{
				System.out.print(k + " ");
			}
			System.out.println();
		}
	}
}
Java Program to Print Left Pascals Number Triangle

This Java example displays the left pascal triangle number pattern using a while loop.

import java.util.Scanner;

public class LeftPascalNumber2 {
	
	private static Scanner sc;
	
	public static void main(String[] args) {
		sc = new Scanner(System.in);
		
		System.out.print("Enter Left Pascals Number Triangle Pattern Rows = ");
		int rows = sc.nextInt();
		
		System.out.println("Printing Left Pascals Triangle Number Pattern");
		int i = 1, j, k;
		
		while (i <= rows ) 
		{
			
			j = i ;
			while ( j < rows ) 
			{
				System.out.print("  ");
				j++;
			}
			
			k = 1;
			while( k <= i) 
			{
				System.out.print(k + " ");
				k++;
			}
			System.out.println();
			i++;
		}
		
		i = rows; 
		while (i >= 1) 
		{
			
			j = i ;
			while (j <= rows) 
			{
				System.out.print("  ");
				j++;
			}
			
			k = 1;
			while( k < i) 
			{
				System.out.print(k + " ");
				k++;
			}
			System.out.println();
			i--;
		}
	}
}
Enter Left Pascals Number Triangle Pattern Rows = 7
Printing Left Pascals Triangle Number Pattern
            1 
          1 2 
        1 2 3 
      1 2 3 4 
    1 2 3 4 5 
  1 2 3 4 5 6 
1 2 3 4 5 6 7 
  1 2 3 4 5 6 
    1 2 3 4 5 
      1 2 3 4 
        1 2 3 
          1 2 
            1 

Java Program to Print Left Pascals Number Triangle using do while loop.

import java.util.Scanner;

public class LeftPascalNumber3 {
	
	private static Scanner sc;
	
	public static void main(String[] args) {
		sc = new Scanner(System.in);
		
		System.out.print("Enter Left Pascals Number Triangle Pattern Rows = ");
		int rows = sc.nextInt();
		
		System.out.println("Printing Left Pascals Triangle Number Pattern");
		int i = 1, j, k;
		
		do
		{
			
			j = i ;
			do 
			{
				System.out.print("  ");

			} while ( j++ < rows );
			
			k = 1;
			do
			{
				System.out.print(k + " ");

			} while( ++k <= i);
			
			System.out.println();

		} while (++i <= rows );
		
		i = rows; 
		do
		{
			
			j = i - 1;
			do
			{
				System.out.print("  ");

			} while (++j <= rows);
			
			k = 1;
			do
			{
				System.out.print(k + " ");

			} while( ++k < i);
			
			System.out.println();

		} while (--i > 1) ;
	}
}
Enter Left Pascals Number Triangle Pattern Rows = 9
Printing Left Pascals Triangle Number Pattern
                  1 
                1 2 
              1 2 3 
            1 2 3 4 
          1 2 3 4 5 
        1 2 3 4 5 6 
      1 2 3 4 5 6 7 
    1 2 3 4 5 6 7 8 
  1 2 3 4 5 6 7 8 9 
    1 2 3 4 5 6 7 8 
      1 2 3 4 5 6 7 
        1 2 3 4 5 6 
          1 2 3 4 5 
            1 2 3 4 
              1 2 3 
                1 2 
                  1