Generate a hollow left angle triangle using alphabets in Python

This shot will discuss generating a hollow left-angle triangle using alphabets in Python.

We can print a plethora of patterns using Python. The essential and only prerequisite is a good understanding of how loops work in Python. Here, we will be using simple for loops to generate a hollow left-angled triangle using alphabets.

Description

A triangle is left-angled if and only if it has one angle equal to 90 degrees on its right side.

Code

Let’s take a look at the below code snippet.

# Number of rows
n = 8
# Loop through rows
for i in range(1,n+1):
# Loop through columns
for j in range(1, n+1):
ch = chr(64+i)
# Printing Pattern
if (i==n-j+1) or (j==n) or (i==n):
print(ch, end=" ")
else:
print(" ", end=" ")
print()

Explanation

  • In line 2, we take the input for the number of rows (i.e., triangle length).

  • In line 5, we create a for loop to iterate through the number of rows.

  • In line 8, we create an inner nested for loop to iterate through the number of columns.

  • In line 9, we define ch, which is used to create alphabets from numbers by using the iterative value of i and the concept of ASCII conversion. The starting value 64+(i=1) has been used, as the ASCII value of A (start of the triangle) is 65.

  • From lines 11 to 14, we create the pattern using conditional statements.

    • i==n-j+1 ⇒ creates the hypotenuse of the triangle.
    • j==n ⇒ creates the perpendicular of the triangle.
    • i==n ⇒ creates the base of the triangle.

    The end statement helps to stay on the same line.

  • In line 15, the print() statement is used to move to the next line.

Free Resources