Spiral Trapezoid of Alphabets
This program prints a trapezoid filled with alphabets in spiral order.
Problem Statement
Write a Java program that prints a trapezoid of 5 rows filled with alphabets in spiral order.
Source Code
| 1 | public class SpiralTrapezoidAlphabets { |
| 2 | public static void main(String[] args) { |
| 3 | int rows=5, cols=9; |
| 4 | char[][] arr=new char[rows][cols]; |
| 5 | int top=0, left=0, bottom=rows-1, right=cols-1; |
| 6 | char ch='A'; |
| 7 | while(top<=bottom && left<=right){ |
| 8 | for(int i=left;i<=right;i++){arr[top][i]=ch++; if(ch>'Z') ch='A';} |
| 9 | top++; |
| 10 | for(int i=top;i<=bottom;i++){arr[i][right]=ch++; if(ch>'Z') ch='A';} |
| 11 | right--; |
| 12 | for(int i=right;i>=left;i--){arr[bottom][i]=ch++; if(ch>'Z') ch='A';} |
| 13 | bottom--; |
| 14 | for(int i=bottom;i>=top;i--){arr[i][left]=ch++; if(ch>'Z') ch='A';} |
| 15 | left++; |
| 16 | } |
| 17 | for(int i=0;i<rows;i++){ |
| 18 | for(int j=0;j<cols;j++){ |
| 19 | if(arr[i][j]!=0) System.out.print(arr[i][j]+" "); |
| 20 | else System.out.print(" "); |
| 21 | } |
| 22 | System.out.println(); |
| 23 | } |
| 24 | } |
| 25 | } |
Program Output
A B C D E F G H I R J Q Z A B C K P Y X W D L O N M L K
Explanation
The same trapezoid-shaped spiral fill is used as the numeric version, but a rotating alphabet character fills each boundary cell, resetting after 'Z', so the trapezoid outline is spelled out with recurring letters.