pi works test | Python Fiddle

import math

def isPrime(number):
	sqrt = math.ceil(math.sqrt(number))

for i in range(2,sqrt + 1):
		if number % i == 0:
			return False
	return True

# this problem is not exactly clear.
# 1. You will start from the top and move downwards to an adjacent number as in below.
# does that mean i can visit the left numbers?
# in this solution i didnt, but i added the code in comments.
def maxPath(filePath):
	
	file = open(filePath, "r")
	numbers = []

for line in file:
		row = line.strip().split()
		# these numbers are currently stored in strings since we took this data from txt file
		# cast it to integer
		# i could do this later but i chose to do it now.
		row = [int(i) for i in row]
		numbers.append(row)

result = solver(numbers,0,0)

file.close()
	return result

def solver(numbers,row,col):
	if row >= len(numbers):
		return 0

number = numbers[row][col]
	if isPrime(number):
		return 0

# if we can go to left number
	# add if col < 0  return 0   below row>= return 0 statement
	# return number + max(solver(numbers, row + 1, col - 1), solver(numbers, row + 1 , col) , solver(numbers, row + 1, col + 1))

return number + max(solver(numbers, row + 1 , col) , solver(numbers, row + 1, col + 1))

res = maxPath("big_input.txt")
print(res)

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