Python: Create maximum number of regions obtained by drawing n given straight lines

Python Basic - 1: Exercise-54 with Solution

If you draw a straight line on a plane, the plane is divided into two regions. For example, if you draw two straight lines in parallel, you get three areas, and if you draw vertically one to the other you get 4 areas.
Write a Python program to create the maximum number of regions obtained by drawing n given straight lines.

Input:
(1 ≤ n ≤ 10,000)
Input number of straight lines (o to exit):
5
Number of regions:
16

Sample Solution:

Python Code:

while True:
    print("Input number of straight lines (o to exit): ")
    n=int(input())
    if n<=0:
        break
    print("Number of regions:") 
    print((n*n+n+2)//2)

Sample Output:

Input number of straight lines (o to exit): 
 5
Number of regions:
16

Flowchart:

Python Code Editor:

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