kencoba

(* 新妻弘，「演習　群・環・体　入門」，共立出版株式会社 より *)
Require Import ZArith.
Open Scope Z_scope.

Theorem thm_1_1 : forall a b c : Z , a + b = a + c -> b = c.
Proof.
  intros a b c H.
  apply Z.add_cancel_l with (p := a).
  assumption.
Qed.

kencoba

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

kencoba

class Request
end

class Read < Request
  attr_reader :var

  def initialize(var)
    @var = var
  end

kencoba

class Request:
    pass


class Read(Request):
    def __init__(self, var):
        self.var = var


class Write(Request):

kencoba

fn main() {
    println!("{n}P{r} = {x}", n = 5, r = 2, x = permutation(5, 2));
    println!("{n}C{r} = {x}", n = 5, r = 2, x = combination(5, 2));
}

pub fn permutation(n: i64, r: i64) -> i64 {
    let mut result = 1;
    for i in (n - r + 1)..=n {
        result *= i;
    }

kencoba

use std::collections::HashMap;

struct Checker {
    memo: HashMap<(i64, i64), i64>,
    max_seat_at_one_table: i64,
}

impl Checker {
    pub fn check(&mut self, remain: i64, pre: i64) -> i64 {
        match &self.memo.get(&(remain, pre)) {

kencoba

#!/usr/bin/env ruby
# usage: ruby download_activity.rb https://www.example.com/ app user passWd\! 12 result.csv
# caution : if your password includes bash's special character ,put a '\' before that char (ex: '!' is '\!').
require "tempfile"
require "uri"


moodle_site = ARGV[0]
app_root = ARGV[1]
username = ARGV[2]

kencoba

# usage:
# $ sudo ruby ./svnadmin.rb #{account} #{password}

account=ARGV[0]
password=ARGV[1]

# create user account.
system "sudo adduser --gecos ',,,' --disabled-login --quiet #{account}"
puts "result of adduser"

kencoba

import java.io.ByteArrayInputStream

import org.antlr.v4.runtime.{CharStream, CharStreams, CommonTokenStream}

/**
 * See original Saumitra's blog.
 * https://saumitra.me/blog/creating-dsl-with-antlr4-and-scala/
 *
 * This code is for Scala 2.13.
 */

kencoba

# -*- mode: ruby -*-
# vi: set ft=ruby :

Vagrant.configure("2") do |config|
  config.vm.box = "ubuntu/bionic64"

  config.vm.network "forwarded_port", guest: 80, host: 8080, host_ip: "127.0.0.1"

  config.vm.network "private_network", ip: "192.168.33.10"