qzchenwl

#include <iostream>
#include <iomanip>
#include <sstream>
#include <vector>
#include <cassert>
#include <cmath>

using namespace std;

class BigInt

qzchenwl

!switch \| `~
keycode 0x31 = backslash bar backslash bar
keycode 0x33 = grave asciitilde grave asciitilde

!switch Super_L Alt_L
clear mod1
clear mod4
keycode 0x85 = Alt_L Meta_L Alt_L Meta_L
keycode 0x40 = Super_L NoSymbol Super_L
add mod1 = Alt_L Alt_R Meta_L

qzchenwl

Trigonometry Helper

A GUI to help you to visualize trigonometric values. Built using ReactJS, SVG and Fraction.js (https://github.com/infusion/Fraction.js).

A Pen by Anthony Dugois on CodePen.

License.

qzchenwl

{-# LANGUAGE ViewPatterns #-}

module CEnum where

import Data.Maybe          ( fromMaybe )
import Text.Read           ( readMaybe )
import Text.Regex.PCRE
import Language.Haskell.TH

normalCons :: Con -> Name

qzchenwl

#!/bin/bash

cat << EOF >> $HOME/.bashrc

export PATH="\$HOME/.local/bin:\$HOME/.cabal/bin:/opt/ghc/7.10.2/bin:/opt/cabal/head/bin:\$PATH"
alias tmux="tmux -2"

EOF

cat << EOF > $HOME/.gitconfig

qzchenwl

/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software

qzchenwl

<input type="file" id="fileinput"/>

qzchenwl

在Ubuntu12.04上安装l2tp/ipsec VPN服务器

因为众所周知的原因，l2tp也已沦陷，本文不再维护。

记录我在Ubuntu服务器上安装l2tp/ipsec VPN的过程，以供日后查询。ipsec用于验证和加密数据包，由openswan提供；l2tp即第二层隧道协议，由xl2tpd提供。

安装相关软件

默认配置即可，后面另有详细介绍。

qzchenwl

module Main where
import Data.List

vertices = "ABCDEFGHIJK"
edges = ["ADB", "AEC", "AFHJ", "AGIK", "BJKC", "BHIE", "DFGE"]
combinations n = filter ((==n) . length) . subsequences
inSameEdge xs = or [ all (`elem` edge) xs | edge <- edges]
isTriangle (a:b:c:[]) = all inSameEdge [[a, b], [a, c], [b, c]] && not (inSameEdge [a, b, c])
triangles = filter isTriangle (combinations 3 vertices)

qzchenwl

awk 'BEGIN{RS="\\+\\+\\+\\+\\+\\+\\+\\+\\+ Incoming Request \\+\\+\\+\\+\\+\\+\\+\\+\\+"; FS="\n"} { match($0, /X-Real-IP: ([0-9\.]+)/, ary); fn=ary[1]".txt"; print $0 >> fn }' debug.log

grep -l 'HTTP/1.1 412 Precondition Failed' *.txt | while read file; do mv $file 412; done