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Several example codes

~1 min read • Updated Oct 6, 2025

Program Overview

This Python program reads an integer n between 1 and 80 and prints a left-aligned triangle using asterisks (*).
Each row contains one more asterisk than the previous row, forming a simple increasing triangle.


Python Code:


# Read n from user
n = int(input("Enter a number between 1 and 80: "))

# Validate input
if 1 <= n <= 80:
    for i in range(1, n + 1):
        print('*' * i)
else:
    print("The number must be between 1 and 80.")

Sample Output for n = 5:


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

Step-by-Step Explanation:

- The user inputs a number n
- The program checks that n is between 1 and 80
- A loop runs from 1 to n, printing i asterisks on each line
- The result is a left-aligned triangle that grows line by line


Written & researched by Dr. Shahin Siami