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