Project Eueler: problem6

問題

The sum of the squares of the first ten natural numbers is,

12 + 22 + ... + 102 = 385
The square of the sum of the first ten natural numbers is,

(1 + 2 + ... + 10)2 = 552 = 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.

回答

res1, res2 = 0 ,0
(1..100).each do |x|
  res1 = res1 + x*x
end
(1..100).each do |x|
  res2 = res2 + x
end
p res2**2 - res1