Python Program to Print Right-Angled Triangle Star Pattern

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Introduction

A right-angled triangle star pattern consists of stars (*) arranged in a triangular shape. This pattern is commonly used to practice loops in programming, where the number of stars increases in each row.

Problem Statement

Create a Python program that:

• Accepts the number of rows for the triangle.
• Prints a right-angled triangle star pattern.

Example:

• Input: rows = 5
• Output:

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

Solution Steps

1. Input the Number of Rows: The user defines how many rows the triangle should have.
2. Use a Loop: The outer loop controls the rows, and an inner part handles printing the stars.
3. Display the Right-Angled Triangle: Print stars in increasing order for each row.

Python Program

# Step 1: Input the number of rows
rows = int(input("Enter the number of rows: "))

# Step 2: Outer loop for rows
for i in range(1, rows + 1):
    # Step 3: Print stars for the current row
    print("*" * i)

Explanation

Step 1: Input the Number of Rows

• The program starts by asking the user to input the number of rows for the right-angled triangle.

Step 2: Outer Loop for Rows

• The outer loop runs from 1 to rows. It controls how many rows are printed.

Step 3: Print Stars

• The loop prints stars (*) in increasing order. In each iteration, the number of stars printed corresponds to the current row number i.

Output Example

For rows = 5, the output will be:

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

For rows = 3, the output will be:

*
**
***

Conclusion

This Python program prints a right-angled triangle star pattern using a loop to control the number of stars printed in each row. This exercise is a simple yet effective way to practice using loops and handling output formatting in Python.