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problem solving/Project Euler in Haskell

ProjectEuler Problem 6 - Sum square difference The sum of the squares of the first ten natural numbers is,12 + 22 + ... + 102 = 385The square of the sum of the first ten natural numbers is,(1 + 2 + ... + 10)2 = 552 = 3025Hence 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 .. 더보기
ProjectEuler Problem 5 - Smallest multiple 2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder.What is the smallest positive number that is evenly divisible by all of the numbers from 1 to 20? This problem is asking what the LCM(least common multiple) of [1..20] is.Haskell provide lcm function in builtin though it is easy to implement.We can compute LCM of more than two numbers by rec.. 더보기
ProjectEuler Problem 4 - Largest palindrome product A palindromic number reads the same both ways. The largest palindrome made from the product of two 2-digit numbers is 9009 = 91 × 99. Find the largest palindrome made from the product of two 3-digit numbers. List of numbers each of which is product of two 3-digit numbers: [x * y | x 더보기
ProjectEuler Problem 3 - Largest prime factor The prime factors of 13195 are 5, 7, 13 and 29.What is the largest prime factor of the number 600851475143 ? A function that returns list of factors:factors n = factors' n 2 where factors' n p | n == 1 = [] | mod n p == 0 = p:factors' (div n p) p | otherwise = factors' n (p + 1) The largest prime factor of 600851475143 is:maximum $ factors 600851475143 in Python 더보기
ProjectEuler Problem 2 - Even Fibonacci numbers Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be: 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-valued terms. The sequence of fibonacci numbers is defined as follow: Writing it in Haskell is not th.. 더보기
ProjectEuler Problem 1 - Multiples of 3 and 5 If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23. Find the sum of all the multiples of 3 or 5 below 1000.It's easy with Haskell's list comprehension sum [x | x 더보기
Haskell - The 1st Note As I worked as a programmer, I've written a lot and been reading many programs written by other authors. Sometimes I found that I enjoys doing this job - understanding, realizing, creating and solving problems. And when I works with other people as a team to solve, figure out, or whatever, I fill like we are talking each other via our code. Code delivers author's idea, considerations, perspectiv.. 더보기

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