Butterfly Pattern with Numbers
This program prints a butterfly pattern with numbers.
Problem Statement
Write a Java program that prints a butterfly pattern with numbers using 5 rows.
Source Code
| 1 | public class ButterflyNumbers { |
| 2 | public static void main(String[] args) { |
| 3 | int n = 5; |
| 4 | for(int i=1; i<=n; i++) { |
| 5 | for(int j=1; j<=i; j++) System.out.print(j); |
| 6 | for(int j=1; j<=2*(n-i); j++) System.out.print(" "); |
| 7 | for(int j=i; j>=1; j--) System.out.print(j); |
| 8 | System.out.println(); |
| 9 | } |
| 10 | for(int i=n; i>=1; i--) { |
| 11 | for(int j=1; j<=i; j++) System.out.print(j); |
| 12 | for(int j=1; j<=2*(n-i); j++) System.out.print(" "); |
| 13 | for(int j=i; j>=1; j--) System.out.print(j); |
| 14 | System.out.println(); |
| 15 | } |
| 16 | } |
| 17 | } |
Program Output
1 1 12 21 123 321 1234 4321 1234554321 1234 4321 123 321 12 21 1 1
Explanation
The first half prints ascending numbers, a shrinking gap of spaces, then descending numbers for each row, and the second half mirrors this with decreasing rows, together forming a numeric butterfly with symmetry.