1   来到网易实习

这些天我一直在后悔一件事情，就是还没看保密协议上面都写有些什么就把它给签了………而且到目前为止我还不知道上面写了些什么。

嗯，透露一下下肯定不是商业机密的事情吧，网易的伙食还不错。

2   晒晒我的 vimrc

分到电脑的那一天花了一个上午装各种软件，其中最耗精力的要数 VIM 了，自己的 vimrc 没有随身带着，又考虑到里面塞满了各种从网上看到的看上去很好玩但实际上一万年用不到一次的设置，所以干脆自己重新写了一份，里面全是每天都会用到的东西，不长：

set nocompatible
source $VIMRUNTIME/mswin.vim
behave mswin

if has("gui_running")
  colo Ifs
  set gfn=consolas:h11
  set go-=m
  set go-=T
  set cursorline
else
  colo blue
  set nocursorline
endif

syntax on
filetype on
filetype indent on
filetype plugin on

map  <space> :
map  <C-j> <C-w><down>
map  <C-k> <C-w><up>
map  <C-h> <C-w><left>
map  <C-l> <C-w><right>
imap <C-j> <down>
imap <C-k> <up>
imap <C-h> <left>
imap <C-l> <right>

let mapleader=";"
map <leader>w :w!<cr>
map <leader>q :close<cr>
map <leader>[ <C-o>
map <leader>] <C-]>
map <leader><space> <C-w>

map <leader>j :bn<cr>
map <leader>k :bp<cr>
map <leader>bd :bd<cr>

map <leader>tn :tabnew<cr>
map <leader>l  :tabn<cr>
map <leader>h  :tabp<cr>
map <C-t>      :tabnew<cr>
map <C-tab>    :tabn<cr>
map <C-S-tab>  :tabp<cr>

map <silent> <leader><cr> :noh<cr>

map <leader>tl :TlistToggle<cr>
map <leader>gf :NERDTree<cr>

set history=50
set autoread
set ts=4
set expandtab
set smarttab
set shiftwidth=4
set autoindent
set smartindent
set cindent
set scrolloff=5
set wildchar=<Tab>
set wildmenu
set cmdheight=1
set ruler
set nu
set lz
set hid
set whichwrap+=<,>,h,l
set ignorecase
set incsearch
set magic
set showmatch
set hlsearch
set laststatus=2
set statusline=\ %P\ %F%m%r%h\ %y\ %w\ \ CWD:\ %{getcwd()}%h\ \ Line:\ %l/%L:%c
set showmatch
set showmode

其中 <space> 和 <leader> 的设置照目前看来貌似很非主流，但是 <space> 不映射成 : 实在是可惜了，毕竟向下滚动有 j 就够了，而且 j 很好用，把 <space> 映射成 : 可以在敲命令的时候感觉十分痛快；另外 ; 就在小拇指上面，用来敲快捷键再方便不过，默认的用于重复 f, t, F, T 的操作也是基本上用不到的，所以，嗯……

这个设置没考虑到 Linux 下的情况，不过除了 gfn 之外其他应该没什么需要改动的吧。另外 Ifs 主题是我在 lettuce 主题的基础上改的，自己喜欢而已。

插件装得不多，因为发现插件多了启动会慢：

• bufexplorer
• c
• mark
• matchit
• NERD_tree
• supertab
• taglist

c.vim 要修改一下，它有个 <leader>lcs 的映射，除了让我的 <leader>l 响应变慢之外啥用途都没有，罪过很大。

——然后用起来就很舒服了。

3   Qt，各种吐槽

最新版本的 Qt 光是安装文件竟然就有 1.5 GB !!! 它完全疯了!!!

有段时间特别喜欢 Qt，因为它的每个类都显得非常漂亮，比如说字符串类里面会提供宽字符和窄字符的转换，再比如说 QImage 类光是构造函数就有这么多种：

• QImage ()
• QImage ( const QSize & size, Format format )
• QImage ( int width, int height, Format format )
• QImage ( uchar * data, int width, int height, Format format )
• QImage ( const uchar * data, int width, int height, Format format )
• QImage ( uchar * data, int width, int height, int bytesPerLine, Format format )
• QImage ( const uchar * data, int width, int height, int bytesPerLine, Format format )
• QImage ( const char * const[] xpm )
• QImage ( const QString & fileName, const char * format = 0 )
• QImage ( const char * fileName, const char * format = 0 )
• QImage ( const QImage & image )

不但功能上一应俱全，而且甚至不需要任何文档，一眼看上去就能知道每个函数是怎么用的。

让人不爽的还是 C++ 的二进制不兼容问题，上次做的一个小实验清楚的说明了想让不同的 C++ 编译器生成的二进制程序共用一个 C++ 类实在是很难的事情；而更早之前的经验表明即使是同一个编译器，不同的版本之间也不见得可以兼容，坑爹啊，也就是说你根本提供不了一个统一的运行时环境，写了个好玩的程序想发给别人装 B，只有每次都把一堆几十 MB 的 dll 和自己几 kb 的程序放在一起才行...这不是比 .Net 还过分吗...

还有，很大程度上托无所不能的 template 的福，C++ 编译的那速度... 上次编译 Qt 4.6 花了 4 个小时左右，后来我专门统计了一下，不算文件头注释和空行，Qt 4.6 一共有 2362083 行代码[1]，按 4 个小时来算的话，那么编译+链接速度平均就是每秒钟 164 行了，还有什么语言能比它更慢一点的！！

怎么好像在对 C++ 吐槽……

……都怪 Qt 太大了， FLTK 这种 kb 级别和谁都能静态链接在一起的图形库，用 C++ 我当然没意见，否则您丫每隔一两月更新一次，每次都扔给我好几 G 的东西，还让我以前的程序面临死翘翘的危险，太过分了。

4   乱七八糟

今天在 cnBeta 上看到一句话 “别人一开源，我们就自主研发了。” 笑死了

“搞ACM的你伤不起[2]” - 一看就知道是大牛手笔

1. 我干了什么

我写了个小程序，用 1.276 秒找出了《银河系漫游指南》和《宇宙尽头的餐馆》的最长公共子串：

the history of every major galactic civilization tends to pass through three distinct and recognizable phases, those of survival, inquiry and sophistication, otherwise known as the how, why and where phases.

用 1.266 秒找出了《宇宙尽头的餐馆》和《再见，谢谢所有的鱼》的最长公共子串：

in the uncharted backwaters of the unfashionable end of the western spiral arm of the galaxy

用 8.671 秒找出了《魔戒》和《1984》的最长公共子串：

. it was inevitable that they should make

用 6.728 秒找出了《飘》和《基本无害》的最长公共子串：

more than anything else in the world.

...

我发现这是件很好玩的事情～

2. 怎么做的

Again，有了 后缀树 ，这样的工作太简单了：

/*
 * Author  : If
 * Date    : Oct/16th/2010
 * License : Boost License v1

Permission is hereby granted, free of charge, to any person or organization
obtaining a copy of the software and accompanying documentation covered by
this license  (the "Software")  to use,  reproduce,  display,  distribute,
execute, and transmit the Software, and to prepare derivative works of the
Software, and to permit third-parties to whom the Software is furnished to
do so, all subject to the following:

The copyright notices in the Software and this entire statement, including
the above license grant, this restriction and the following disclaimer,
must be included in all copies of the Software, in whole or in part, and
all derivative works of the Software, unless such copies or derivative
works are solely in the form of machine-executable object code generated by
a source language processor.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED,  INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
*/

#include "suffixtree.h"
#include <algorithm>
#include <iterator>
#include <iostream>
#include <fstream>
#include <cctype>
#include <cstdio>
#include <string>
#include <vector>
#include <ctime>
using namespace std;

static void ticToc_(bool s)
{
    static clock_t start_ = clock();
    if(s) {
        start_ = clock();
    } else {
        clock_t end_=clock();
        std::cerr
            << (end_ - start_) << " ticks"
            << "    (" << (end_ - start_) * (1000.)/CLOCKS_PER_SEC <<"ms)"
            << std::endl;
    }
}

inline void tic()
{
    ticToc_(true);
}

inline void toc()
{
    ticToc_(false);
}

struct Info
{
    vector<int> belongTo;
};

typedef Node<char, Info>       NodeT;
typedef SuffixTree<char, Info> STree;

// 初始化节点的从属属性。
void initInfo(NodeT& leaf)
{
    NodeT* node = leaf.parent;
    int    nth  = leaf.belongTo;
    while ( node->parent!=node && (
            node->info.belongTo.empty() ||
            node->info.belongTo.back()!=nth )) {
        node->info.belongTo.push_back(nth);
        node=node->parent;
    }
}

void printPath(NodeT const* node)
{
    if(node->parent!=node)
        printPath(node->parent);
    copy(node->str, node->str+node->len,
         ostream_iterator<char>(cout));
}

// 将连续的空白字符转换成单个空格；将大写全转换为小写。
void filter(char * text, int & len)
{
    char*p=text,*q=text;
    for(;q<text+len;++p,++q){
        if(*q>='A'&&*q<='Z') {
            *p=*q-'A'+'a';
        } else if(isspace(*q)) {
            *p=' ';
            while(isspace(*q))
                ++q;
            --q;
        } else {
            *p=*q;
        }
    }
    len = p-text;
}

struct LetsRock
{
    NodeT const*& result;
    int   longestNow;
    int   nStrings;
    LetsRock(int n, NodeT const*& root):
        result(root),
        longestNow(0),
        nStrings(n)
    { }
    void operator()(NodeT const& node) {
        if (node.depth + node.len > longestNow &&
            node.info.belongTo.size()==nStrings) {
            longestNow = node.depth + node.len;
            result     = &node;
        }
    }
};

int main(int c,char**v)
{
    STree tree;
    tic();
    for(int i=1;i<c;++i) {
        cerr<<"reading "<<v[i]<<" ...\n";
        FILE*  file = fopen(v[i],"r");
        string content;
        char   buf[8192];
        int    bytesRead=0;
        int    bytesTotal=0;
        while((bytesRead=fread(buf,1,8192,file))==8192) {
            filter(buf,bytesRead);
            content.append(buf,bytesRead);
            bytesTotal += bytesRead;
        }
        if(bytesRead) {
            filter(buf,bytesRead);
            content.append(buf,bytesRead);
            bytesTotal += bytesRead;
        }
        fclose(file);
        cerr<<"done. ( " << bytesTotal <<" bytes )\n";
        cerr<<"adding to suffix tree ...\n";
        tree.addString(content);
        cerr<<"done.\n";
    }
    NodeT const* ans = tree.root();
    tree.eachLeaf(initInfo);
    LetsRock fun(c-1,ans);
    tree.dfs(fun);
    printPath(ans);
    cout<<endl;
    toc();
    return 0;
}

1. 我干了什么

我写了个程序，运行时内存占用峰值为 323 MB，耗时 6.582s，从 2,827,372 字节的《魔戒》全本中找出了不算空格、大小写敏感的情况下出现两次或更多的最长子串：

All that is gold does not glitter,

Not all those who wander are lost;

The old that is strong does not wither,

Deep roots are not reached by the frost.

 

From the ashes a fire shall be woken,

A light from the shadows shall spring;

Renewed shall be blade that was broken,

The crownless again shall be king.

耗时 7.022 秒，内存占用峰值 351 MB，从 3,872,493 字节的 sqlite 3.6.22 的合并 c 文件中找到了最长重复子串：(忽略空格)

.c****************//**************Beginfileos_common.h********************
****** *************//***2004May22****Theauthordisclaimscopyrighttothissou
rcecode.Inpla ceof**alegalnotice,hereisablessing:****Mayyoudogoodandnotevi
l.**Mayyoufindforgiv enessforyourselfandforgiveothers.**Mayyousharefreely,
nevertakingmorethanyougive.  *********************************************
*********************************** ****Thisfilecontainsmacrosandalittlebi
tofcodethatiscommonto**alloftheplatform-sp ecificfiles(os_*.c)andis#includ
edintothose**files.****Thisfileshouldbe#includedb ytheos_*.cfilesonly.Itis
nota**generalpurposeheaderfile.*/#ifndef_OS_COMMON_H_#de fine_OS_COMMON_H_
/***AtleasttwobugshaveslippedinbecausewechangedtheMEMORY_DEBUG* *macrotoSQ
LITE_DEBUGandsomeoldermakefileshavenotyetmadethe**switch.Thefollowingc ode
shouldcatchthisproblematcompile-time.*/#ifdefMEMORY_DEBUG#error"TheME
MORY_DEB UGmacroisobsolete.UseSQLITE_DEBUGinstead."#endif#ifdefSQLITE
_DEBUGSQLITE_PRIVATE intsqlite3OSTrace=0;#defineOSTRACE1(X)if(sqlite3OSTra
ce)sqlite3DebugPrintf(X)#de fineOSTRACE2(X,Y)if(sqlite3OSTrace)sqlite3Debu
gPrintf(X,Y)#defineOSTRACE3(X,Y,Z) if(sqlite3OSTrace)sqlite3DebugPrintf(X,
Y,Z)#defineOSTRACE4(X,Y,Z,A)if(sqlite3OST race)sqlite3DebugPrintf(X,Y,Z,A)
#defineOSTRACE5(X,Y,Z,A,B)if(sqlite3OSTrace)sqli te3DebugPrintf(X,Y,Z,A,B)
#defineOSTRACE6(X,Y,Z,A,B,C)\if(sqlite3OSTrace)sqlite3D ebugPrintf(X,Y,Z,A
,B,C)#defineOSTRACE7(X,Y,Z,A,B,C,D)\if(sqlite3OSTrace)sqlite3D ebugPrintf(
X,Y,Z,A,B,C,D)#else#defineOSTRACE1(X)#defineOSTRACE2(X,Y)#defineOSTRA CE3(
X,Y,Z)#defineOSTRACE4(X,Y,Z,A)#defineOSTRACE5(X,Y,Z,A,B)#defineOSTRACE6(X,
Y, Z,A,B,C)#defineOSTRACE7(X,Y,Z,A,B,C,D)#endif/***Macrosforperformancetra
cing.Norm allyturnedoff.Onlyworks**oni486hardware.*/#ifdefSQLITE_PERFORMAN
CE_TRACE/***hwti me.hcontainsinlineassemblercodeforimplementing**high-perf
ormancetimingroutines.* //**************Includehwtime.hinthemiddleofos_com
mon.h****************//******* *******Beginfilehwtime.h*******************
***********************//***2008May27 ****Theauthordisclaimscopyrighttothi
ssourcecode.Inplaceof**alegalnotice,hereisab lessing:****Mayyoudogoodandno
tevil.**Mayyoufindforgivenessforyourselfandforgiveo thers.**Mayyousharefre
ely,nevertakingmorethanyougive.*************************** ***************
******************************************Thisfilecontainsinlinea smcodefo
rretrieving"high-performance"**countersforx86classCPUs.*/#ifndef
_HWTIME_ H_#define_HWTIME_H_/***Thefollowingroutineonlyworksonpentium-clas
s(ornewer)proce ssors.**ItusestheRDTSCopcodetoreadthecyclecountvalueoutoft
he**processorandreturn sthatvalue.Thiscanbeusedforhigh-res**profiling.*/#i
f(defined(__GNUC__)||defined( _MSC_VER))&&\(defined(i386)||defined
(__i386__)||defined(_M_IX86))#ifdefined(__GN UC__)__inline__sqlite_uint64s
qlite3Hwtime(void){unsignedintlo,hi;__asm____volati le__("rdtsc"
:"=a"(lo),"=d"(hi));return(sqlite_uint64)hi<<32|
lo;}#elifdefined(_MS C_VER)__declspec(naked)__inlinesqlite_uint64__cdeclsq
lite3Hwtime(void){__asm{rdt scret;returnvalueatEDX:EAX}}#endif#elif(define
d(__GNUC__)&&defined(__x86_64__))_ _inline__sqlite_uint64sqlite3Hw
time(void){unsignedlongval;__asm____volatile__("r dtsc":"=A
"(val));returnval;}#elif(defined(__GNUC__)&&defined(__ppc__))
__inline__ sqlite_uint64sqlite3Hwtime(void){unsignedlonglongretval;unsigne
dlongjunk;__asm__ __volatile__("\n\1:mftbu%1\n\mftb%L0\n\mftbu%0\n\cm
pw%0,%1\n\bne1b":"=r"(retval) ,"=r"(junk));return
retval;}#else#errorNeedimplementationofsqlite3Hwtime()foryour platform./**
*Tocompilewithoutimplementingsqlite3Hwtime()foryourplatform,**youcan remov
etheabove#errorandusethefollowing**stubfunction.Youwilllosetimingsupportfo
r many**ofthedebuggingandtestingutilities,butitshouldat**leastcompileandru
n.*/SQLI TE_PRIVATEsqlite_uint64sqlite3Hwtime(void){return((sqlite_uint64)
0);}#endif#endi f/*!defined(_HWTIME_H_)*//**************Endofhwtime.h*****
********************** *******************//**************Continuingwherew
eleftoffinos_common.h******** **********/staticsqlite_uint64g_start;static
sqlite_uint64g_elapsed;#defineTIMER_ STARTg_start=sqlite3Hwtime()#defineTI
MER_ENDg_elapsed=sqlite3Hwtime()-g_start#de fineTIMER_ELAPSEDg_elapsed#els
e#defineTIMER_START#defineTIMER_END#defineTIMER_EL APSED((sqlite_uint64)0)
#endif/***IfwecompilewiththeSQLITE_TESTmacroset,thenthefo llowingblock**of
codewillgiveustheabilitytosimulateadiskI/Oerror.This**isusedfort estingthe
I/Orecoverylogic.*/#ifdefSQLITE_TESTSQLITE_APIintsqlite3_io_error_hit=0 ;/
*TotalnumberofI/OErrors*/SQLITE_APIintsqlite3_io_error_hardhit=0;/*Numbero
fnon -benignerrors*/SQLITE_APIintsqlite3_io_error_pending=0;/*Countdowntof
irstI/Oerro r*/SQLITE_APIintsqlite3_io_error_persist=0;/*TrueifI/Oerrorspe
rsist*/SQLITE_APIi ntsqlite3_io_error_benign=0;/*Trueiferrorsarebenign*/SQ
LITE_APIintsqlite3_diskfu ll_pending=0;SQLITE_APIintsqlite3_diskfull=0;#de
fineSimulateIOErrorBenign(X)sqli te3_io_error_benign=(X)#defineSimulateIOE
rror(CODE)\if((sqlite3_io_error_persist &&sqlite3_io_error_hit)\||
sqlite3_io_error_pending--==1)\{local_ioerr();CODE;}st aticvoidlocal_ioerr
(){IOTRACE(("IOERR\n"));sqlite3_io_error_hit++;if(!sqlite3_io _e
rror_benign)sqlite3_io_error_hardhit++;}#defineSimulateDiskfullError(CODE)
\if( sqlite3_diskfull_pending){\if(sqlite3_diskfull_pending==1){\local_ioe
rr();\sqlit e3_diskfull=1;\sqlite3_io_error_hit=1;\CODE;\}else{\sqlite3_di
skfull_pending--;\ }\}#else#defineSimulateIOErrorBenign(X)#defineSimulateI
OError(A)#defineSimulateD iskfullError(A)#endif/***Whentesting,keepacounto
fthenumberofopenfiles.*/#ifdefSQ LITE_TESTSQLITE_APIintsqlite3_open_file_c
ount=0;#defineOpenCounter(X)sqlite3_ope n_file_count+=(X)#else#defineOpenC
ounter(X)#endif#endif/*!defined(_OS_COMMON_H_) *//**************Endofos_co
mmon.h*******************************************//** ************Continui
ngwhereweleftoffinos_ 

正如之前在 后缀树的介绍 中说过的那样，俺想要弄出个能压缩 C 程序代码的工具，而上面的就是原型了：找出出现多次且较长的子串， #define 一下，重复多次，差不多了。

2. 怎么做的

有了后缀树，这样的工作可真是简单啊：

/*
 * Author  : If
 * Date    : Oct/14th/2010
 * Version : 0.0.1
 */
/*
Permission is hereby granted, free of charge, to any person or organization
obtaining a copy of the software and accompanying documentation covered by
this license  (the "Software")  to use,  reproduce,  display,  distribute,
execute, and transmit the Software, and to prepare derivative works of the
Software, and to permit third-parties to whom the Software is furnished to
do so, all subject to the following:

The copyright notices in the Software and this entire statement, including
the above license grant, this restriction and the following disclaimer,
must be included in all copies of the Software, in whole or in part, and
all derivative works of the Software, unless such copies or derivative
works are solely in the form of machine-executable object code generated by
a source language processor.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED,  INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
*/

#include "suffixtree.h"
#include <algorithm>
#include <iterator>
#include <iostream>
#include <string>
#include <cmath>
#include <ctime>
using namespace std;

static void ticToc_(bool s)
{
    static clock_t start_ = clock();
    if(s) {
        start_ = clock();
    } else {
        clock_t end_=clock();
        std::cerr
            << (end_ - start_) << " ticks"
            << "    (" << (end_ - start_) * (1000.)/CLOCKS_PER_SEC <<"ms)"
            << std::endl;
    }
}

inline void tic()
{
    ticToc_(true);
}

inline void toc()
{
    ticToc_(false);
}


struct Info {
    int cv,depth,isLeaf;
    Info():cv(-1),depth(-1),isLeaf(0){}
};

typedef Node<char,Info> NodeT;

void initInfo(NodeT& node) {
    node.info.depth = node.depth + node.len;
    if(node.branches.empty()){
        node.info.isLeaf = 1;
        node.info.cv = node.leafNum;
    } else {
        node.info.isLeaf = 0;
        NodeT* p = node.branches[0];
        if(p->info.cv==-1) {
            initInfo(*p);
        }
        node.info.cv = p->info.cv;
    }
}

void printPath(NodeT const* node)
{
    if(node->parent!=node) {
        printPath(node->parent);
    }
    copy(node->str, node->str+node->len, ostream_iterator<char>(cout));
}

struct LetsHaveFun
{
    NodeT const*& result;
    LetsHaveFun(NodeT const*& root):result(root){}
    void operator()(NodeT& node){
        if(!node.info.isLeaf &&  // more than once
            node.depth != 0 &&   // not root
            node.info.depth > result->info.depth && // better
            abs(node.info.cv - node.branches.back()->info.cv) >=
                node.info.depth  // do not overlap
        ) {
            this->result = &node;
        }
    }
};

int main(int c,char**v) {
    if(c>2)
        return 1;
    SuffixTree<char, Info> stree;
    NodeT const* ans = stree.root();
    LetsHaveFun fun(ans);
    string source;
    if(c==2&&v[1][0]=='-') {
        if(v[1][1]=='S') // do not skip white space
            cin>>noskipws;
        else if(v[1][1]=='s')
            cin>>skipws;
        else
            return 1;
    } else {
        return 1;
    }

    copy(istream_iterator<char>(cin), istream_iterator<char>(),
         back_inserter(source));
    tic();
    stree.addString(source);
    stree.dfs(initInfo);
    stree.dfs(fun);
    printPath(ans);
    cout<<endl;
    toc();
}

3. Question

这次有问题顺便想要请教一下高人们，在上面的代码中有一段让我很不爽：

struct LetsHaveFun
{
    NodeT const*& result;
    ...

我的本意是想用 NodeT const* result ; 然而那么做的话 stree.dfs(fun) 这句话结束之后 fun.result 又回到了 root （LetsHaveFun::operator() 中 result 的确会变的！），百思不得其解，似乎碰到了某个语法的黑暗角落；然而在这个问题上 VC2008 和 GCC 4.5.0 竟然表现得出奇的一致以至于我开始怀疑自己了，谁来救救我？

4. PostScript

suffixtree.h 全部内容在我的 后缀树的介绍 中。

5. Update

Ubuntu 威武，同样的代码，同样的文件系统，同样的计算机配置，同样的编译器，同样的编译选项，在 Ubuntu 上面，此处(Win7)耗时 6.5 秒的程序变得只要 4.5 秒了，Astonishing