rhysd

#include <iostream>

constexpr int f( int n, int i )
{
  return n<=0 ? 0 : (n + f(n-i, i));
}


static constexpr int MAX = 1000 - 1;

rhysd

class Main{
  public static void main(String[] args){
    int max = 1000;
    int total = 0;
    int i;

    i = 3;
    while(i<max){
      total += i;
      i += 3;

rhysd

putStr $ show $ sum [x|x<-[1..999], rem x 3 == 0 || rem x 5 == 0]

rhysd

mergeSort :: Ord a => [a] -> [a]
mergeSort [] = []
mergeSort [x] = [x]
mergeSort xs = merge (mergeSort l) (mergeSort r)
    where
        s = length xs `div` 2
        (l,r) = splitAt s xs
        merge :: Ord a => [a] -> [a] -> [a]
        merge [] ys = ys
        merge xs [] = xs

rhysd

# path を通す
(setq load-path (cons "~/.emacs.d/site-lisp" load-path))
(setq load-path (cons "~/.emacs.d/site-lisp/melpa" load-path))

# パッケージ管理を使うための初期化
(require 'package)                                                                                                                                                                                       
                                                                                                                                                                                                         
; Add package-archives                                                                                                                                                                                   
(add-to-list 'package-archives '("melpa" . "http://melpa.milkbox.net/packages/") t)                                                                                                                      
                                                                 

rhysd

#include <iostream>
#include <array>
#include <string>
#include <algorithm>
#include <numeric>

int main()
{
    std::array<size_t, 100> arr;
    std::iota(arr.begin(), arr.end(), 1);

rhysd

Twitter::configure do |config|
    config.consumer_key = 'piyo'
    config.consumer_secret = 'poyo'
    config.oauth_token = 'foo'
    config.oauth_token_secret = 'bar'
end

# と書いていたのが，

Twitter::configure do

rhysd

    a = 1
    b = 'a'

    case [a,b]
    when [1,'b'] then "hoge"
    when [2,'a'] then "huga"
    when [1,'a'] then "poyo"
    else "puyo" end
    
    #=> "poyo"

rhysd

isPalindromeNum :: Int -> Bool
isPalindromeNum n = s == reverse s
    where s = show n

main = putStrLn . show . maximum $ [x*y| x<-[100..999],y<-[x..999], isPalindromeNum $ x*y]

rhysd

#include <iostream>
#include <string>

bool is_palindrome(int const i)
{
    auto s = std::to_string(i);
    for(auto f=s.begin(), l=s.end()-1; f<=l; ++f, --l){
        if(*f!=*l) return false;
    }
    return true;