Python Challenges: Compute the sum of the numbers on the diagonals in a 1001 by 1001 spiral formed

Last update on December 21 2024 07:49:50 (UTC/GMT +8 hours)

Starting with the number 1 and moving to the right in a clockwise direction a 5 by 5 spiral is formed as follows:

21	22	23	24	25
20	7	8	9	10
19	6	1	2	11
18	5	4	3	12
17	16	15	14	13

Diagonals Numbers: 21 + 7 + 1 + 3 + 13 + 25 + 9 + 5 + 17 = 101
It can be verified that the sum of the numbers on the diagonals is 101.
Write a Python program to compute the sum of the numbers on the diagonals in a 1001 by 1001 spiral formed in the above way.

Sample Solution:

Python Code:

MAX_SIZE = 1001  
result = 1 
result += sum(4 * i * i - 6 * (i - 1) for i in range(3, MAX_SIZE + 1, 2))
print(str(result))

Sample Output:

669171001

Flowchart:

#Ref: https://bit.ly/2GZmz51

Python Code Editor:

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