Pattern Printing in Python

A comprehensive guide to understanding and creating different pattern-printing programs in Python. Perfect for beginners who want to strengthen their logic-building and looping concepts.

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📌 Table of Contents

S.No.	Pattern Name	Problem Link	Solution Link
1	Square Star Pattern	Problem	Solution
2	Left Triangle Pattern	Problem	Solution
3	Right Triangle Pattern	Problem	Solution
4	Number Triangle Pattern	Problem	Solution
5	Same Number Triangle Pattern	Problem	Solution
6	Inverted Number Pattern	Problem	Solution
7	Number Sequence Pattern	Problem	Solution
8	Pyramid Pattern	Problem	Solution
9	Inverted Pyramid	Problem	Solution
10	Diamond Pattern	Problem	Solution
11	Number Pyramid with Dashes	Problem	Solution
12	Reverse Number Pyramid	Problem	Solution
13	Hollow Square Pattern	Problem	Solution
14	Hollow Rectangle Pattern	Problem	Solution
15	Hollow Diamond Pattern	Problem	Solution
16	Butterfly Pattern	Problem	Solution
17	Number Pattern with Dashes	Problem	Solution
18	Complex Number Pattern	Problem	Solution
19	Inverted Triangle Pattern	Problem	Solution
20	Combined Triangle Pattern	Problem	Solution

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📚 What You Will Learn

• Basics of loops for pattern printing
• Star (*) patterns
• Number patterns
• Alphabet patterns
• Pyramid patterns
• Hollow patterns
• Advanced patterns
• Common mistakes and how to fix them
• Practice exercises

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⭐ Basic Patterns

1. Square Star Pattern

*****
*****
*****
*****
*****

Solution:

rows = 5
cols = 5
for i in range(rows):
    for j in range(cols):
        print("*", end="")
    print()

2. Left Triangle Pattern

*
**
***
****
*****

Solution:

rows = 5
for i in range(rows):
    for j in range(i + 1):
        print("*", end="")
    print()

3. Right Triangle Pattern

    *
   **
  ***
 ****
*****

Solution:

rows = 5
for i in range(rows):
    print(" " * (rows - i - 1) + "*" * (i + 1))

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🔢 Number Patterns

4. Number Triangle Pattern

1
12
123
1234
12345

Solution:

rows = 5
for i in range(1, rows + 1):
    for j in range(1, i + 1):
        print(j, end="")
    print()

5. Same Number Triangle Pattern

1
22
333
4444
55555

Solution:

for i in range(5):
    for j in range(i + 1):
        print(i + 1, end="")
    print()

6. Inverted Number Pattern

12345
1234
123
12
1

Solution:

for i in range(5):
    for j in range(1, 6 - i):
        print(j, end="")
    print()

7. Number Sequence Pattern

1 
2 3 
4 5 6 
7 8 9 10 
11 12 13 14 15

Solution:

num = 0
for i in range(1, 6):
    for j in range(i):
        num += 1
        print(f"{num} ", end="")
    print()

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🔺 Pyramid Patterns

8. Pyramid Pattern

    *
   ***
  *****
 *******
*********

Solution:

rows = 5
for i in range(rows):
    print(" " * (rows - i - 1) + "*" * (2 * i + 1))

9. Inverted Pyramid

*********
 *******
  *****
   ***
    *

Solution:

rows = 5
for i in range(rows, 0, -1):
    print(" " * (rows - i) + "*" * (2 * i - 1))

10. Diamond Pattern

    *
   ***
  *****
 *******
*********
 *******
  *****
   ***
    *

Solution:

# Upper part
for i in range(5):
    for j in range(5 - i):
        print(" ", end="")
    for k in range(i + 1):
        print("*", end="")
    for m in range(i):
        print("*", end="")
    print()

# Lower part
for i in range(4):
    for j in range(i + 2):
        print(" ", end="")
    for k in range(4 - i):
        print("*", end="")
    for m in range(3 - i):
        print("*", end="")
    print()

11. Number Pyramid with Dashes

----1
---12
--123
-1234
12345

Solution:

for k in range(1, 6):
    for m in range(5 - k):
        print("-", end="")
    for n in range(1, k + 1):
        print(n, end="")
    print()

12. Reverse Number Pyramid

----1
---21
--321
-4321
54321

Solution:

for k in range(1, 6):
    for m in range(5 - k):
        print("-", end="")
    for n in range(k, 0, -1):
        print(n, end="")
    print()

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🕳️ Hollow Patterns

13. Hollow Square Pattern

*****
*   *
*   *
*   *
*****

Solution:

rows = 5
cols = 5
for i in range(rows):
    for j in range(cols):
        if i == 0 or i == rows - 1 or j == 0 or j == cols - 1:
            print("*", end="")
        else:
            print(" ", end="")
    print()

14. Hollow Rectangle Pattern

****
*  *
*  *
****

Solution:

for i in range(1, 5):
    for j in range(1, 5):
        if 2 <= i <= 3 and 2 <= j <= 3:
            print(" ", end="")
        else:
            print("*", end="")
    print()

15. Hollow Diamond Pattern

**********
****  ****
***    ***
**      **
*        *
*        *
**      **
***    ***
****  ****
**********

Solution:

# Upper Part
for i in range(5):
    for j in range(5 - i):
        print("*", end="")
    for k in range(i):
        print(" ", end="")
    for m in range(i):
        print(" ", end="")
    for n in range(5 - i):
        print("*", end="")
    print("")

# Lower Part
for i in range(1, 6):
    for j in range(i):
        print("*", end="")
    for k in range(5 - i):
        print(" ", end="")
    for m in range(5 - i):
        print(" ", end="")
    for n in range(i):
        print("*", end="")
    print("")

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🔥 Advanced Patterns

16. Butterfly Pattern

*        *
**      **
***    ***
****  ****
**********
****  ****
***    ***
**      **
*        *

Solution:

# Upper Part
for i in range(1, 6):
    for j in range(i):
        print("*", end="")
    for k in range(5 - i):
        print(" ", end="")
    for m in range(5 - i):
        print(" ", end="")
    for n in range(i):
        print("*", end="")
    print()

# Lower Part
for i in range(4):
    for j in range(4 - i):
        print("*", end="")
    for k in range(i + 1):
        print(" ", end="")
    for m in range(i + 1):
        print(" ", end="")
    for n in range(4 - i):
        print("*", end="")
    print()

17. Number Pattern with Dashes

1------1
12----21
123--321
12344321

Solution:

for i in range(1, 5):
    for j in range(1, i + 1):
        print(j, end="")
    print("-" * (4 * 2 - i * 2), end="")
    for k in range(i, 0, -1):
        print(k, end="")
    print()

18. Complex Number Pattern

4 4 4 4 4 4 4 
4 3 3 3 3 3 4 
4 3 2 2 2 3 4 
4 3 2 1 2 3 4 
4 3 2 2 2 3 4 
4 3 3 3 3 3 4 
4 4 4 4 4 4 4 

Solution:

for i in range(1, 8):
    for j in range(1, 8):
        if (i == 2 and 2 <= j <= 6) or (i == 6 and 2 <= j <= 6) or (3 <= i <= 5 and j == 2) or (3 <= i <= 5 and j == 6):
            print("3 ", end="")
        elif (j == 3 and 3 <= i <= 5) or (j == 5 and 3 <= i <= 5) or (i == 3 and 3 <= j <= 5) or (i == 5 and 3 <= j <= 5):
            print("2 ", end="")
        elif i == 4 and j == 4:
            print("1 ", end="")
        else:
            print("4 ", end="")
    print()

19. Inverted Triangle Pattern

*****
****
***
**
*

Solution:

for i in range(5):
    for j in range(5 - i):
        print("*", end="")
    print()

20. Combined Triangle Pattern

*
**
***
****
*****
****
***
**
*

Solution:

for i in range(5):
    for j in range(i + 1):
        print("*", end="")
    print()
    
for i in range(5):
    for j in range(4 - i):
        print("*", end="")
    print()

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❗ Common Mistakes Students Make

1. Forgetting end=""

This prints each symbol on a new line.

2. Using wrong indentation

Python is indentation-sensitive — wrong spaces break your program.

3. Misunderstanding ranges

Examples:

• range(5) → 0 to 4
• range(1,5) → 1 to 4
• range(5,0,-1) → 5 to 1

4. Incorrect loop boundaries

Always test edge cases for your loops.

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📝 Practice Exercises

Try to code these yourself:

1. Hollow pyramid
2. Pascal's triangle
3. Hourglass pattern
4. Floyd's triangle
5. Spiral pattern
6. Zigzag pattern
7. Heart pattern
8. Arrow patterns

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🎯 Tips for Success

1. Start simple: Begin with basic patterns before moving to complex ones
2. Understand the logic: Don't just copy code - understand the pattern structure
3. Use variables: Make your code flexible by using variables for rows/columns
4. Debug step by step: Print intermediate values to understand what's happening
5. Practice regularly: Pattern printing improves with consistent practice

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📚 Resources

• Python Official Documentation
• GeeksforGeeks Pattern Programs
• W3Schools Python Tutorial

Happy Coding! 🚀