ngn999

`(a list have (+ 2 3) elements)  => (a list have (+ 2 3) elements)
'(a list have (+ 2 3) elements)  =>  (a list have (+ 2 3) elements)

`(a list have ,(+ 2 3) elements) => (a list have 5 elements)

ngn999

 p = reinterpret_cast<const unsigned char *>(szKey);
        while (*p) {
            res = (res << 7) + (res >> 25) + *p++;
        }

// 相当于,res这个int32将前面8位移到后面去了, eg.   1101001xxxxxxxxxxxxx,就成了,xxxxxxxxxxxxx110100  

ngn999

(defun squar (x)
  "return x * x"
  (* x x))

;; scroll-ahead
;; scroll-behind


;;switch-to-buffer
;;other-buffer

ngn999

/*
		12306 Auto Login => A javascript snippet to help you auto login 12306.com.
		Copyright (C) 2011 Kevintop
		
		Includes jQuery
		Copyright 2011, John Resig
		Dual licensed under the MIT or GPL Version 2 licenses.
		http://jquery.org/license

		Includes 12306.user.js

ngn999

(fn [coll]
  (apply concat
    (map (fn [x] (list x x)) coll)))

ngn999

(fn [coll n]
  (apply concat
    (map #(for [x (range n)] %) coll)))

ngn999

(fn range2 [ss ee]
  ((fn iter [s e res]
    (if (>= s e)
      res
      (do
      (iter (inc s) e (concat res (list s))))))
      ss ee '()))

ngn999

(defn max2 [ & coll ]
  (if (empty? coll)
    nil
    ((fn iter [s m]
       (if (empty? s)
         m
         (if (>= (first s) m)
           (iter (rest s) (first s))
           (iter (rest s) m))))
     (rest coll) (first coll))

ngn999

git log --graph

git log --graph --oneline

ngn999

向后查找:

echo "pt=1234" | grep -Po '(?<=pt=)\d+'

向前查找:

echo "1234pt=" | grep -Po '\d+(?=pt=)'