Java pattern programs are valuable for improving coding skills, enhancing logical thinking, and reinforcing looping concepts. They are commonly used in Java interviews to assess a programmer’s logic and problem-solving abilities. Various designs can be achieved when printing Java pattern programs. Mastering pattern programming requires a strong understanding of looping constructs in Java, such as the for loop and do-while loop. In this section, we will explore the process of printing patterns in Java.
Java pattern program has been classified into three categories:
- Start Pattern
- Number Pattern
- Character Pattern
When designing logic for a pattern program, it is beneficial to start by visually representing the pattern using blocks, as illustrated in the provided image. This visual representation offers a clear understanding of the pattern’s structure.
Pattern programs typically involve two or more loops, with the number of loops depending on the complexity of the pattern and the desired logic. The first loop is responsible for iterating through the rows, while the second loop handles the columns. In pattern programs, Java for loop is commonly employed due to its versatility and convenience. By leveraging the for loop, programmers can effectively generate pattern designs in Java.
In the aforementioned pattern, the row is represented by the variable “I,” while the column is denoted by “j.” Observing the pattern, we notice that the first row prints a single star, the second row prints two stars, and so on. The highlighted blocks signify the presence of spaces within the pattern.
Now, let’s proceed to develop the logic for the given pattern. In the subsequent code snippet, we will initialize the row and column values to 0. However, it is also possible to start them from 1, depending on your preference.
for(int i=0; i<row; i++)
{
for(int j=0; j<=i; j++)
{
System.out.print("* ");
}
System.out.println();
Let’s see the execution of the code step by step, for n=4 (the number of rows we want to print).
Iteration 1:
For i=0, 0<4 (true) For j=0, j<=0 (true)
The initial print statement is responsible for printing a star in the first row, while the subsequent println statement generates the necessary spaces and moves the cursor to the next line.
*
Now the value of i and j is increased to 1.
Iteration 2:
For i=1, 1<4 (true) For j=1, 1<=1 (true)
In the given pattern, the first print statement is used to print two stars in the second row. After that, the second println statement is utilized to print the corresponding spaces and move the cursor to the next line.
* * *
Now the value of i and j is increased to 2.
Iteration 3:
For i=2, 2<4 (true) For j=2, 2<=2 (true)
Within the pattern, the first print statement is responsible for printing three stars in the third row. Following that, the second println statement is utilized to print the required spaces and move the cursor to the next line.
* * * * * *
Now the value of i and j is increased to 3.
Iteration 4:
For i=3, 3<4 (true) For j=3, 3<=3 (true)
About the pattern, the first print statement is utilized to print four stars in the fourth row. Subsequently, the second println statement is employed to print the necessary spaces and move the cursor to the next line.
* * * * * * * * * *
Now the value of i and j is increased to 4.
For i=4, 4<4 (false)
The program execution will conclude once the value of “i” becomes equal to the total number of rows in the pattern.
Star Pattern Program in Java
1. Right Triangle Star Pattern
public class RightTrianglePattern
{
public static void main(String args[])
{
//i for rows and j for columns
//row denotes the number of rows you want to print
int i, j, row=6;
//outer loop for rows
for(i=0; i<row; i++)
{
//inner loop for columns
for(j=0; j<=i; j++)
{
//prints stars
System.out.print("* ");
}
//throws the cursor in a new line after printing each line
System.out.println();
}
}
}
Output:
* * * * * * * * * * * * * * * * * * * * *
2. Left Triangle Star Pattern
public class LeftTrianglePattern
{
public static void main(String args[])
{
//i for rows and j for columns
//row denotes the number of rows you want to print
int i, j, row = 6;
//Outer loop work for rows
for (i=0; i<row; i++)
{
//inner loop work for space
for (j=2*(row-i); j>=0; j--)
{
//prints space between two stars
System.out.print(" ");
}
//inner loop for columns
for (j=0; j<=i; j++ )
{
//prints star
System.out.print("* ");
}
//throws the cursor in a new line after printing each line
System.out.println();
}
}
}
Output:
*
* *
* * *
* * * *
* * * * *
* * * * * *
3. Pyramid Star Pattern
public class PyramidPattern
{
public static void main(String args[])
{
//i for rows and j for columns
//row denotes the number of rows you want to print
int i, j, row = 6;
//Outer loop work for rows
for (i=0; i<row; i++)
{
//inner loop work for space
for (j=row-i; j>1; j--)
{
//prints space between two stars
System.out.print(" ");
}
//inner loop for columns
for (j=0; j<=i; j++ )
{
//prints star
System.out.print("* ");
}
//throws the cursor in a new line after printing each line
System.out.println();
}
}
}
Output:
*
* *
* * *
* * * *
* * * * *
* * * * * *
4. Diamond Shape Pattern
import java.util.Scanner;
public class DiamondPattern
{
public static void main(String args[])
{
int row, i, j, space = 1;
System.out.print("Enter the number of rows you want to print: ");
Scanner sc = new Scanner(System.in);
row = sc.nextInt();
space = row - 1;
for (j = 1; j<= row; j++)
{
for (i = 1; i<= space; i++)
{
System.out.print(" ");
}
space--;
for (i = 1; i <= 2 * j - 1; i++)
{
System.out.print("*");
}
System.out.println("");
}
space = 1;
for (j = 1; j<= row - 1; j++)
{
for (i = 1; i<= space; i++)
{
System.out.print(" ");
}
space++;
for (i = 1; i<= 2 * (row - j) - 1; i++)
{
System.out.print("*");
}
System.out.println("");
}
}
}
Output:
Enter the number of rows you want to print: 5
*
***
*****
*******
*********
*******
*****
***
*
5. Downward Triangle Star Pattern
public class DownwardTrianglePattern
{
public static void main(String[] args)
{
int rows=7;
//inner loop
for (int i= rows-1; i>=0 ; i--)
{
//outer loop
for (int j=0; j<=i; j++)
{
//prints star and space
System.out.print("*" + " ");
}
//throws the cursor in the next line after printing each line
System.out.println();
}
}
}
Output:
* * * * * * * * * * * * * * * * * * * * * * * * * * * *
6. Mirrored Right Triangle Star Pattern
public class MirroredRightTrianglePattern
{
public static void main(String[] args)
{
int n=7;
//inner loop
for (int i= 0; i<= n; i++)
{
//outer loop
for (int j=1; j<=n-i; j++)
{
System.out.print(" ");
}
for (int k=0;k<=i;k++)
{
System.out.print("*");
}
System.out.println("");
}
}
}
Output:
*
**
***
****
*****
******
*******
********
7. Reverse Pyramid Star Pattern
public class ReversePyramidPattern
{
public static void main(String[] args)
{
int rows=8;
for (int i= 0; i<= rows-1; i++)
{
for (int j=0; j<=i; j++)
{
System.out.print(" ");
}
for (int k=0; k<=rows-1-i; k++)
{
System.out.print("*" + " ");
}
System.out.println();
}
}
}
Output:
* * * * * * * *
* * * * * * *
* * * * * *
* * * * *
* * * *
* * *
* *
*
8. Right Down Mirror Star Pattern
public class RightDownMirrorPattern
{
public static void main(String args[])
{
int row=7;
for (int i= row; i>= 1; i--)
{
for (int j=row; j>i;j--)
{
System.out.print(" ");
}
for (int k=1;k<=i;k++)
{
System.out.print("*");
}
System.out.println("");
}
}
}
Output:
*******
******
*****
****
***
**
*
9. Right Pascal’s Triangle
import java.util.Scanner;
public class RightPascalTrianglePattern
{
public static void main(String[] args)
{
int i, j, rows;
Scanner sc = new Scanner(System.in);
System.out.print("Enter the number of rows you want to print: ");
rows = sc.nextInt();
for (i= 0; i<= rows-1; i++)
{
for (j=0; j<=i; j++)
{
System.out.print("*"+ " ");
}
System.out.println("");
}
for (i=rows-1; i>=0; i--)
{
for(j=0; j <= i-1;j++)
{
System.out.print("*"+ " ");
}
System.out.println("");
}
}
}
Output:
Enter the number of rows you want to print: 5 * * * * * * * * * * * * * * * * * * * * * * * * *
10. Left Pascal’s Triangle
import java.util.Scanner;
public class LeftPascalTrianglePattern
{
public static void main(String[] args)
{
int i, j, k, rows;
Scanner sc = new Scanner(System.in);
System.out.print("Enter the number of rows you want to print: ");
rows = sc.nextInt();
for (i= 1; i<= rows ; i++)
{
for (j=i; j <rows ;j++)
{
System.out.print(" ");
}
for (k=1; k<=i;k++)
{
System.out.print("*");
}
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("*");
}
System.out.println("");
}
sc.close();
}
}
Output:
Enter the number of rows you want to print: 7
*
**
***
****
*****
******
*******
******
*****
****
***
**
*
11. Sandglass Star Pattern
import java.util.Scanner;
public class SandglassPattern
{
public static void main(String[] args)
{
int i, j, k, n;
Scanner sc = new Scanner(System.in);
System.out.print("Enter the number of rows you want to print: ");
n = sc.nextInt();
for (i= 0; i<= n-1 ; i++)
{
for (j=0; j<i; j++)
{
System.out.print(" ");
}
for (k=i; k<=n-1; k++)
{
System.out.print("*" + " ");
}
System.out.println("");
}
for (i= n-1; i>= 0; i--)
{
for (j=0; j<i; j++)
{
System.out.print(" ");
}
for (k=i; k<=n-1; k++)
{
System.out.print("*" + " ");
}
System.out.println("");
}
sc.close();
}
}
Output:
Enter the number of rows you want to print: 7
* * * * * * *
* * * * * *
* * * * *
* * * *
* * *
* *
*
*
* *
* * *
* * * *
* * * * *
* * * * * *
* * * * * * *
12. Alphabet Star Pattern
import java.util.*;
public class AlphabetPattern
{
public static void main(String[] args)
{
int i, j, n=8;
// Outer for loop for number of lines
for (i = 0; i<=n; i++)
{
// Inner for loop for logic execution
for (j = 0; j<= n / 2; j++)
{
// prints two vertical lines
if ((j == 0 || j == n / 2) && i != 0 ||
// print first line of alphabet
i == 0 && j != n / 2 ||
// prints middle line
i == n / 2)
System.out.print("*");
else
System.out.print(" ");
}
System.out.println();
}
}
}
Output:
**** * * * * * * ***** * * * * * * * *
13. Triangle Star Pattern
import java.util.Scanner;
public class TrianglePattern
{
public static void main(String[] args)
{
int i, j, k, rows=9;
for (i=1; i<= rows ; i++)
{
for (j = i; j < rows ; j++)
{
System.out.print(" ");
}
for (k = 1; k <= (2*i -1) ;k++)
{
if(k==1 || i == rows || k==(2*i-1))
{
System.out.print("*");
}
else
{
System.out.print(" ");
}
}
System.out.println("");
}
}
}
Output:
*
* *
* *
* *
* *
* *
* *
* *
*****************
14. Down Triangle Pattern
import java.util.Scanner;
public class DownTrianglePattern
{
public static void main(String[] args)
{
int i, j, k, rows=9;
for (i=rows; i>= 1 ; i--)
{
for (j = i; j<rows ; j++)
{
System.out.print(" ");
}
for (k = 1; k <= (2*i -1) ;k++)
{
if( k==1 || i == rows || k==(2*i-1))
{
System.out.print("*");
}
else
{
System.out.print(" ");
}
}
System.out.println("");
}
}
}
Output:
*****************
* *
* *
* *
* *
* *
* *
* *
*
15. Diamond Star Pattern
import java.util.*;
public class Main
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("Enter the number of rows you want to print: ");
int rows = sc.nextInt();
for (int i = 1; i <= rows; i++) {
for (int j = rows; j > i; j--) {
System.out.print(" ");
}
System.out.print("*");
for (int k = 1; k < 2 * (i - 1); k++) {
System.out.print(" ");
}
if (i == 1) {
System.out.println("");
} else {
System.out.println("*");
}
}
for (int i = rows - 1; i >= 1; i--) {
for (int j = rows; j > i; j--) {
System.out.print(" ");
}
System.out.print("*");
for (int k = 1; k < 2 * (i - 1); k++) {
System.out.print(" ");
}
if (i == 1) {
System.out.println("");
} else {
System.out.println("*");
}
}
}
}
Output:
Enter the number of rows you want to print: 7
*
* *
* *
* *
* *
* *
* *
* *
* *
* *
* *
* *
*
Number Pattern Programs in Java
1. Pattern-1
public class Pattern1
{
public static void main(String args[])
{
int i, j,number, n=7;
//loop for rows
for(i=0; i<n; i++)
{
number=1;
//loop for columns
for(j=0; j<=i; j++)
{
//prints num
System.out.print(number+ " ");
//incrementing the value of number
number++;
}
//throws the cursor at the next line after printing each row
System.out.println();
}
}
}
Output:
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
2. Pattern-2
public class Pattern2
{
public static void main(String[] args)
{
int i, j, k = 1;
//inner loop
for (i = 1; i <= 7; i++)
{
//outer loop
for (j = 1; j< i + 1; j++)
{
//prints the value of k
System.out.print(k++ + " ");
}
//throws the cursor at the next line
System.out.println();
}
}
}
Output:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
3. Pattern-3
public class Pattern3
{
public static void main(String[] args)
{
int n = 8; //n is the number of rows you want to print
for (int i = 0; i < n; i++)
{
int number = 1;
System.out.printf("%" + (n - i) * 2 + "s", "");
for (int j = 0; j <= i; j++)
{
System.out.printf("%4d", number);
number = number * (i - j) / (j + 1);
}
System.out.println();
}
}
}
Output:
1
1 1
1 2 1
1 3 3 1
1 4 6 4 1
1 5 10 10 5 1
1 6 15 20 15 6 1
1 7 21 35 35 21 7 1
4. Pattern-4
public class Pattern4
{
public static void main(String[] args)
{
for (int i = 1; i <= 4; i++)
{
int n = 8;
for (int j = 1; j<= n - i; j++)
{
System.out.print(" ");
}
for (int k = i; k >= 1; k--)
{
System.out.print(k);
}
for (int l = 2; l <= i; l++)
{
System.out.print(l);
}
System.out.println();
}
for (int i = 3; i >= 1; i--)
{
int n = 10;
for (int j = 0; j<= n - i; j++)
{
System.out.print(" ");
}
for (int k = i; k >= 1; k--)
{
System.out.print(k);
}
for (int l = 2; l <= i; l++)
{
System.out.print(l);
}
System.out.println();
}
}
}
Output:
1 212 32123 4321234 32123 212 1
5. Pattern-5
import java.util.*;
public class Pattern5
{
public static void main(String[] args)
{
int i, j, rows;
Scanner sc = new Scanner(System.in);
System.out.print("Enter the number of rows you want to print: ");
rows = sc.nextInt();
for (i = 1; i <= rows; i++)
{
for (j = 1; j <= i; j++)
{
System.out.print(i+" ");
}
System.out.println();
}
}
}
Output:
Enter the number of rows you want to print: 10 1 2 2 3 3 3 4 4 4 4 5 5 5 5 5 6 6 6 6 6 6 7 7 7 7 7 7 7 8 8 8 8 8 8 8 8 9 9 9 9 9 9 9 9 9 10 10 10 10 10 10 10
6. Pattern-6
import java.util.*;
public class Pattern6
{
public static void main(String[] args)
{
int i, j, rows;
Scanner sc = new Scanner(System.in);
System.out.print("Enter the number of rows youy want to print: ");
rows = sc.nextInt();
for (i = rows; i >= 1; i--)
{
for (j = rows; j >= i; j--)
{
System.out.print(j+" ");
}
System.out.println();
}
}
}
Output:
Enter the number of rows youy want to print: 6 6 6 5 6 5 4 6 5 4 3 6 5 4 3 2 6 5 4 3 2 1
7. Pattern-7
import java.util.Scanner;
public class Pattern7
{
public static void main(String[] args)
{
int i, j, n;
Scanner sc = new Scanner(System.in);
System.out.print("Enter the number of rows you want to print: ");
n = sc.nextInt();
for (i = 1; i <= n; i++)
{
for (j = i; j >= 1; j--)
{
System.out.print(j+" ");
}
System.out.println();
}
}
}
Output:
Enter the number of rows you want to print: 8 1 2 1 3 2 1 4 3 2 1 5 4 3 2 1 6 5 4 3 2 1 7 6 5 4 3 2 1 8 7 6 5 4 3 2 1
8. Pattern-8
public class Pattern8
{
public static void main(String[] args)
{
int rows=9; //number of rows to print
for (int i = 1; i <= rows; i++)
{
int num;
if(i%2 == 0)
{
num = 0;
for (int j = 1; j <= rows; j++)
{
System.out.print(num);
num = (num == 0)? 1 : 0;
}
}
else
{
num = 1;
for (int j = 1; j <= rows; j++)
{
System.out.print(num);
num = (num == 0)? 1 : 0;
}
}
System.out.println();
}
}
}
Output:
101010101 010101010 101010101 010101010 101010101 010101010 101010101 010101010 101010101
9. Pattern-9
import java.util.Scanner;
public class Pattern9
{
public static void main(String[] args)
{
int i, j, rows=9;
for (i = 1; i <= rows; i++)
{
for (j = 1; j <= i; j++)
{
if(j%2 == 0)
{
System.out.print(0);
}
else
{
System.out.print(1);
}
}
System.out.println();
}
}
}
Output:
1 10 101 1010 10101 101010 1010101 10101010 101010101
10. Pattern-10
public class Pattern10
{
public static void main(String[] args)
{
int n = 10;
for (int i = 1; i <= n; i++)
{
for (int j = 1; j < i; j++)
{
System.out.print(" ");
}
for (int k = i; k <= n; k++)
{
System.out.print(k+" ");
}
System.out.println();
}
for (int i = n-1; i >= 1; i--)
{
for (int j = 1; j < i; j++)
{
System.out.print(" ");
}
for (int k = i; k <= n; k++)
{
System.out.print(k+" ");
}
System.out.println();
}
}
}
Output:
1 2 3 4 5 6 7 8 9 10
2 3 4 5 6 7 8 9 10
3 4 5 6 7 8 9 10
4 5 6 7 8 9 10
5 6 7 8 9 10
6 7 8 9 10
7 8 9 10
8 9 10
9 10
10
9 10
8 9 10
7 8 9 10
6 7 8 9 10
5 6 7 8 9 10
4 5 6 7 8 9 10
3 4 5 6 7 8 9 10
2 3 4 5 6 7 8 9 10
1 2 3 4 5 6 7 8 9 10
11. Pattern-11
public class Pattern11
{
public static void main(String[] args)
{
int rows=8;
//Prints upper half pattern
for (int i = 1; i <= rows; i++)
{
for (int j = 1; j <= i; j++)
{
System.out.print(j+" ");
}
System.out.println();
}
//prints lower half pattern
for (int i = rows-1; i >= 1; i--)
{
for (int j = 1; j <= i; j++)
{
System.out.print(j+" ");
}
System.out.println();
}
}
}
Output:
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 1 2 3 4 5 6 1 2 3 4 5 1 2 3 4 1 2 3 1 2 1
12. Pattern-12
public class Pattern12
{
public static void main(String[] args)
{
int rows=9;
for (int i = 1; i <= rows; i++)
{
for (int j = rows; j >= i; j--)
{
System.out.print(j+" ");
}
System.out.println();
}
}
}
Output:
9 8 7 6 5 4 3 2 1 9 8 7 6 5 4 3 2 9 8 7 6 5 4 3 9 8 7 6 5 4 9 8 7 6 5 9 8 7 6 9 8 7 9 8 9
13. Pattern-13
public class Pattern13
{
public static void main(String[] args)
{
int i, j, rows=9;
for (i = rows; i >= 1; i--)
{
for (j = 1; j <= i; j++)
{
System.out.print(j+" ");
}
System.out.println();
}
}
}
Output:
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
14. Pattern-14
public class Pattern14
{
public static void main(String[] args)
{
int rows=7, i, j;
for (i = rows; i >= 1; i--)
{
for (j = i; j >= 1; j--)
{
System.out.print(j+" ");
}
System.out.println();
}
}
}
Output:
7 6 5 4 3 2 1 6 5 4 3 2 1 5 4 3 2 1 4 3 2 1 3 2 1 2 1 1
15. Pattern-15
public class Pattern15
{
public static void main(String[] args)
{
int i, j, rows=9;
for (i = 1; i <= rows; i++)
{
//Prints first half of the row
for (j = 1; j <= i; j++)
{
System.out.print(j+" ");
}
//Prints second half of the row
for (j = i-1; j >= 1; j--)
{
System.out.print(j+" ");
}
System.out.println();
}
}
}
Output:
1 1 2 1 1 2 3 2 1 1 2 3 4 3 2 1 1 2 3 4 5 4 3 2 1 1 2 3 4 5 6 5 4 3 2 1 1 2 3 4 5 6 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8 9 8 7 6 5 4 3 2 1
16. Pattern-16
public class Pattern16
{
public static void main(String[] args)
{
int i, j, rows=9;
//Prints upper half pattern
for (i = rows; i >= 1; i--)
{
for (j = 1; j <= i; j++)
{
System.out.print(j+" ");
}
System.out.println();
}
//Prints lower half pattern
for (i = 2; i <= rows; i++)
{
for (j = 1; j <= i; j++)
{
System.out.print(j+" ");
}
System.out.println();
}
}
}
Output:
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 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
17. Pattern-17
public class Pattern17
{
public static void main(String[] args)
{
int rows=9;
//Prints upper half pattern
for (int i = 1; i <= rows; i++)
{
//Prints i spaces at the beginning of each row
for (int j = 1; j < i; j++)
{
System.out.print(" ");
}
//Prints i to rows value at the end of each row
for (int j = i; j <= rows; j++)
{
System.out.print(j);
}
System.out.println();
}
//Prints lower half pattern
for (int i = rows-1; i >= 1; i--)
{
//Prints i spaces at the beginning of each row
for (int j = 1; j < i; j++)
{
System.out.print(" ");
}
//Prints i to rows value at the end of each row
for (int j = i; j <= rows; j++)
{
System.out.print(j);
}
System.out.println();
}
}
}
Output:
123456789
23456789
3456789
456789
56789
6789
789
89
9
89
789
6789
56789
456789
3456789
23456789
123456789
18. Pattern-18
public class Pattern18
{
public static void main(String[] args)
{
int rows=8;
for (int i = 1; i <= rows; i++)
{
for (int j = 1; j <= rows-i; j++)
{
System.out.print(1);
}
for (int j = 1; j <= i; j++)
{
System.out.print(i);
}
System.out.println();
}
}
}
Output:
11111111 11111122 11111333 11114444 11155555 11666666 17777777 88888888
19. Pattern-19
public class Pattern19
{
public static void main(String args[])
{
int rows=9;
for (int i = 1; i <= rows; i++)
{
int num = i;
for (int j = 1; j <= i; j++)
{
System.out.print(num+" ");
num = num+rows-j;
}
System.out.println();
}
}
}
Output:
1 2 10 3 11 18 4 12 19 25 5 13 20 26 31 6 14 21 27 32 36 7 15 22 28 33 37 40 8 16 23 29 34 38 41 43 9 17 24 30 35 39 42 44 45
20. Pattern-20
public class Pattern20
{
public static void main(String[] args)
{
int i, j, k, rows=9;
for(i=1;i< rows+1 ;i++)
{
for(j=i; j < rows+1 ;j++)
{
System.out.print(j + " ");
}
for(k=1; k < i ;k++)
{
System.out.print(k + " ");
}
System.out.println();
}
}
}
Output:
1 2 3 4 5 6 7 8 9 2 3 4 5 6 7 8 9 1 3 4 5 6 7 8 9 1 2 4 5 6 7 8 9 1 2 3 5 6 7 8 9 1 2 3 4 6 7 8 9 1 2 3 4 5 7 8 9 1 2 3 4 5 6 8 9 1 2 3 4 5 6 7 9 1 2 3 4 5 6 7 8
21. Pattern-21
import java.util.Scanner;
public class Pattern21
{
public static void main(String[] args)
{
int i, j, min, n; //n is the number up to you want to print
System.out.print("Enter the value of n: ");
Scanner sc= new Scanner(System.in);
n=sc.nextInt();
//loo for upper left part
for (i = 1; i <= n; i++)
{
for (j = 1; j <= n; j++)
{
min = i < j ? i : j;
System.out.print(n - min + 1+ " ");
}
//loop for upper right part
for (j = n - 1; j >= 1; j--)
{
min = i < j ? i : j;
System.out.print(n - min + 1+ " ");
}
System.out.println();
}
//loop for lower left part
for (i = n - 1; i >= 1; i--)
{
for (j = 1; j <= n; j++)
{
min = i < j ? i : j;
System.out.print(n - min + 1+ " ");
}
//loop for lower right part
for (j = n - 1; j >= 1; j--)
{
min = i < j ? i : j;
System.out.print(n - min + 1+ " ");
}
System.out.println();
}
}
}
Output:
Enter the value of n: 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 6 6 6 6 6 6 6 6 6 6 6 7 7 6 5 5 5 5 5 5 5 5 5 6 7 7 6 5 4 4 4 4 4 4 4 5 6 7 7 6 5 4 3 3 3 3 3 4 5 6 7 7 6 5 4 3 2 2 2 3 4 5 6 7 7 6 5 4 3 2 1 2 3 4 5 6 7 7 6 5 4 3 2 2 2 3 4 5 6 7 7 6 5 4 3 3 3 3 3 4 5 6 7 7 6 5 4 4 4 4 4 4 4 5 6 7 7 6 5 5 5 5 5 5 5 5 5 6 7 7 6 6 6 6 6 6 6 6 6 6 6 7 7 7 7 7 7 7 7 7 7 7 7 7 7
Character Pattern Program in Java
1. Right Triangle Alphabetic Pattern
public class RightAlphabaticPattern
{
public static void main(String[] args)
{
int alphabet = 65; //ASCII value of capital A is 65
//inner loop for rows
for (int i = 0; i <= 8; i++)
{
//outer loop for columns
for (int j = 0; j <= i; j++)
{
//adds the value of j in the ASCII value of A and prints the corresponding alphabet
System.out.print((char) (alphabet + j) + " ");
}
System.out.println();
}
}
}
Output:
A A B A B C A B C D A B C D E A B C D E F A B C D E F G A B C D E F G H A B C D E F G H I
2. Repeating Alphabet Pattern
public class RepeatingPattern
{
public static void main(String[] args)
{
int letter = 65; //ASCII value of capital A is 65
//inner loop for rwos
for (int i = 0; i<= 9; i++)
{
//outer loop for columns
for (int j = 0; j <= i; j++)
{
//prints the character
System.out.print((char) letter + " ");
}
letter++;
System.out.println();
}
}
}
Output:
A B B C C C D D D D E E E E E F F F F F F G G G G G G G H H H H H H H H I I I I I I I I I J J J J J J J J J J
3. K-shape Alphabet Pattern
public class KshapePattern
{
public static void main(String[] args)
{
for (int i = 8; i >= 0; i--)
{
int alphabet = 65;
for (int j = 0; j <= i; j++)
{
System.out.print((char) (alphabet + j) + " ");
}
System.out.println();
}
for (int i = 0; i<= 8; i++)
{
int alphabet = 65;
for (int j = 0; j <= i; j++)
{
System.out.print((char) (alphabet + j) + " ");
}
System.out.println();
}
}
}
Output:
A B C D E F G H I A B C D E F G H A B C D E F G A B C D E F A B C D E A B C D A B C A B A A A B A B C A B C D A B C D E A B C D E F A B C D E F G A B C D E F G H A B C D E F G H I
4. Triangle Character Pattern
public class TriangleCharacterPattern
{
public static void main(String[] args)
{
for (int i = 0; i <= 8; i++)
{
int alphabet = 65;
for (int j = 8; j > i; j--)
{
System.out.print(" ");
}
for (int k = 0; k <= i; k++)
{
System.out.print((char) (alphabet + k) + " ");
}
System.out.println();
}
}
}
Output:
A
A B
A B C
A B C D
A B C D E
A B C D E F
A B C D E F G
A B C D E F G H
A B C D E F G H I
5. Diamond Character Pattern
import java.util.Scanner;
public class DiamondCharacterPattern {
public static void main(String[] args) {
char[] alphabet = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'};
int alphabet_number = 0;
String[] diamond = new String[26]; // array of strings
System.out.print("Enter a Character between A to Z: ");
Scanner reader = new Scanner(System.in);
try {
char user_alphabet = reader.next("[A-Z]").charAt(0);
// Search for letter number in the alphabet array
for (int i = 0; i < alphabet.length; i++) {
if (alphabet[i] == user_alphabet) {
alphabet_number = i;
break;
}
}
// Construct diamond
for (int i = 0; i <= alphabet_number; i++) {
diamond[i] = "";
// Add initial spaces
for (int j = 0; j < alphabet_number - i; j++) {
diamond[i] += " ";
}
// Add alphabet
diamond[i] += alphabet[i];
// Add space between letters
if (alphabet[i] != 'A') {
for (int j = 0; j < 2 * i - 1; j++) {
diamond[i] += " ";
}
// Add alphabet
diamond[i] += alphabet[i];
}
// Draw the first part of the diamond
System.out.println(diamond[i]);
}
for (int i = alphabet_number - 1; i >= 0; i--) {
// Draw the second part of the diamond (reverse order)
System.out.println(diamond[i]);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
reader.close();
}
}
}
Output:
Enter a Character between A to Z: H
A
B B
C C
D D
E E
F F
G G
H H
G G
F F
E E
D D
C C
B B
A
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