c++

Libcurl 简明使用指南

Michael — Tue, 29 Nov 2005 09:03:00 GMT

Libcurl为一个免费开源的，客户端url传输库，支持FTP，FTPS，TFTP，HTTP，HTTPS，GOPHER，TELNET，DICT，FILE和LDAP，跨平台，支持Windows，Unix，Linux等，线程安全，支持Ipv6。并且易于使用。

http://curl.haxx.se/libcurl/

从http://curl.haxx.se/libcurl/ 下载一个稳定的版本，注意选择OS。

编译libcurl

下载下来的是源码包，需要编译。

解压zip文件，进入curl-7.14.0\lib目录（我下载的是7.14.0）。

编译Debug版本。新建一个批处理bat文件，如buildDebug.bat，内容如下：

call "C:\Program Files\Microsoft Visual Studio\VC98\Bin\vcvars32.bat"

set CFG=debug-dll-ssl-dll-zlib-dll

set OPENSSL_PATH=E:\SSL\openssl-0.9.7e

set ZLIB_PATH=E:\zip\zlib123

nmake -f Makefile.vc6

其输出：libcurld_imp.lib, libcurld.dll

编译Release版本。新建一个批处理文件BuildRelease.bat，内容如下：

call "C:\Program Files\Microsoft Visual Studio\VC98\Bin\vcvars32.bat"

set CFG=release-dll-ssl-dll-zlib-dll

set OPENSSL_PATH=E:\SSL\openssl-0.9.7e

set ZLIB_PATH=E:\zip\zlib123

nmake -f Makefile.vc6

其输出：libcurl_imp.lib, libcurl.dll

上面编译的是libcurl的 dll，使用OpenSSL Dll版本和Zlib Dll版本。如果没有，可以从www.openssl.org 或者http://www.zlib.net/ 下载。

如果需要编译其他版本，可查看Makefile.vc6，设定相应的CFG 参数即可。

商业软件使用libcurl时，只需要包含其copywrite声明即可。

Sample

#include <stdio.h>
#include "../curl-7.14.0/include/curl/curl.h"
#pragma comment(lib, "../curl-7.14.0/lib/libcurl_imp.lib")

int main(void)
{
  curl = curl_easy_init();
  if(curl) {

    CURLcode res;
    res = curl_easy_setopt(curl, CURLOPT_PROXY, "Test-pxy08:8080");
    res = curl_easy_setopt(curl, CURLOPT_PROXYTYPE, CURLPROXY_HTTP);
    res = curl_easy_setopt(curl, CURLOPT_URL, "http://www.vckbase.com");
    res = curl_easy_perform(curl);

    if(CURLE_OK == res) {
      char *ct;
      /* ask for the content-type */
      /* http://curl.haxx.se/libcurl/c/curl_easy_getinfo.html */
      res = curl_easy_getinfo(curl, CURLINFO_CONTENT_TYPE, &ct);

      if((CURLE_OK == res) && ct)
        printf("We received Content-Type: %s ", ct);
    }

    /* always cleanup */
    curl_easy_cleanup(curl);
  }
  return 0;
}

已知bugs

不支持SOCKS4。

SOCKS5实现有缺陷，导致必须设置用户和密码。

连接proxy过程不能设置超时。

Google™ Code Jam - 中国编程挑战赛模拟题三

Michael — Sat, 26 Nov 2005 14:20:00 GMT

Google™ Code Jam - 中国编程挑战赛

Problem Statement

When editing a single line of text, there are four keys that can be used to move the cursor: end, home, left-arrow and right-arrow. As you would expect, left-arrow and right-arrow move the cursor one character left or one character right, unless the cursor is at the beginning of the line or the end of the line, respectively, in which case the keystrokes do nothing (the cursor does not wrap to the previous or next line). The home key moves the cursor to the beginning of the line, and the end key moves the cursor to the end of the line.

You will be given a int, N, representing the number of character in a line of text. The cursor is always between two adjacent characters, at the beginning of the line, or at the end of the line. It starts before the first character, at position 0. The position after the last character on the line is position N. You should simulate a series of keystrokes and return the final position of the cursor. You will be given a string where characters of the string represent the keystrokes made, in order. 'L' and 'R' represent left and right, while 'H' and 'E' represent home and end.

Definition

Class:	CursorPosition
Method:	getPosition
Parameters:	string, int
Returns:	int
Method signature:	int getPosition(string keystrokes, int N)
(be sure your method is public)

Constraints

keystrokes will be contain between 1 and 50 'L', 'R', 'H', and 'E' characters, inclusive.

N will be between 1 and 100, inclusive.

Examples

"ERLLL"

Returns: 7

First, we go to the end of the line at position 10. Then, the right-arrow does nothing because we are already at the end of the line. Finally, three left-arrows brings us to position 7.

"EHHEEHLLLLRRRRRR"

Returns: 2

All the right-arrows at the end ensure that we end up at the end of the line.

"ELLLELLRRRRLRLRLLLRLLLRLLLLRLLRRRL"

Returns: 3

"RRLEERLLLLRLLRLRRRLRLRLRLRLLLLL"

Returns: 12

This problem statement is the exclusive and proprietary property of TopCoder, Inc. Any unauthorized use or reproduction of this information without the prior written consent of TopCoder, Inc. is strictly prohibited. (c)2003, TopCoder, Inc. All rights reserved.

我的解答

#include <string>

using namespace std;

const char LEFT = 'L';
const char RIGHT = 'R';
const char HOME = 'H';
const char END = 'E';

class CursorPosition
{
public:
    int getPosition(string keystrokes, int N);
};

int CursorPosition::getPosition(string keystrokes, int N)
{
    int nCurrPos = 0;

    int i=0;
    for (i = 0; i < keystrokes.length(); i++)
    {
        if (LEFT == keystrokes.at(i))
        {
            if (nCurrPos > 0)
            {
                nCurrPos--;
            }
        }
        else if (RIGHT == keystrokes.at(i))
        {
            if (nCurrPos < N)
            {
                nCurrPos++;
            }
        }
        else if (HOME == keystrokes.at(i))
        {
            nCurrPos = 0;
        }
        else if (END == keystrokes.at(i))
        {
            nCurrPos = N;
        }
    }

    return nCurrPos;
}

Google™ Code Jam - 中国编程挑战赛模拟题二

Michael — Sat, 26 Nov 2005 14:18:00 GMT

Google™ Code Jam - 中国编程挑战赛 http://www.topcoder.com/gcjc_zh

题目如下：

Problem Statement

A square matrix is a grid of NxN numbers. For example, the following is a 3x3 matrix:

 4 3 5
 2 4 5
 0 1 9

One way to represent a matrix of numbers, each of which is between 0 and 9 inclusive, is as a row-major string. To generate the string, simply concatenate all of the elements from the first row followed by the second row and so on, without any spaces. For example, the above matrix would be represented as "435245019".

You will be given a square matrix as a row-major string. Your task is to convert it into a vector <string>, where each element represents one row of the original matrix. Element i of the vector <string> represents row i of the matrix. You should not include any spaces in your return. Hence, for the above string, you would return {"435","245","019"}. If the input does not represent a square matrix because the number of characters is not a perfect square, return an empty vector <string>, {}.

Definition

Class:	MatrixTool
Method:	convert
Parameters:	string
Returns:	vector <string>
Method signature:	vector <string> convert(string s)
(be sure your method is public)

Constraints

s will contain between 1 and 50 digits, inclusive.

Examples

"435245019"

Returns: {"435", "245", "019" }

The example above.

"9"

Returns: {"9" }

"0123456789"

Returns: { }

This input has 10 digits, and 10 is not a perfect square.

"3357002966366183191503444273807479559869883303524"

Returns: {"3357002", "9663661", "8319150", "3444273", "8074795", "5986988", "3303524" }

#include <string>
#include <vector>
#include <math.h>

using namespace std;

class MatrixTool
{
public:
    vector<string> convert(string s);
};

vector<string> MatrixTool::convert(string s)
{
    vector<string> vecResult;

    int iLength = s.length();
    int iYinzi = (int)sqrt(iLength);
    if (iYinzi * iYinzi != iLength)
    {
        return vecResult;
    }

    int i = 0;
    for (; i < iYinzi; i++)
    {
        string strTmp = s.substr(iYinzi*i, iYinzi);
        vecResult.push_back(strTmp);
    }

    return vecResult;
}

模拟题比较简单。