# Sum square difference
#
# The sum of the squares of the first ten natural numbers 
# is, 1^2 + 2^2 + ... + 10^2 = 385.
#
# The square of the sum of the first ten natural numbers 
# is, (1 + 2 + ... + 10^2) = 55^2 = 3025.
#
# Hence the difference between the sum of the squares of 
# the first ten natural numbers and the square of the sum 
# is 3025 - 385 = 2640.
#
# Find the difference between the sum of the squares of the 
# first one hundred natural numbers and the square of the sum.
#
# https://projecteuler.net/problem=6

# test
nlist = list(range(1, 11))

sum_square = 0
for n in nlist:
	sum_square += (n ** 2)

square_sum = sum(nlist) ** 2

assert(square_sum - sum_square == 2640)

# solution
nlist = list(range(1, 101))

sum_square = 0
for n in nlist:
	sum_square += (n ** 2)

square_sum = sum(nlist) ** 2

print(square_sum - sum_square)
# 25164150