﻿<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:trackback="http://madskills.com/public/xml/rss/module/trackback/" xmlns:wfw="http://wellformedweb.org/CommentAPI/" xmlns:slash="http://purl.org/rss/1.0/modules/slash/"><channel><title>C++博客-Merlin-随笔分类-C++</title><link>http://www.cppblog.com/yunduan5158/category/174.html</link><description>Life was like a box of chocolates. You never know what you're gonna get.</description><language>zh-cn</language><lastBuildDate>Wed, 21 May 2008 14:12:58 GMT</lastBuildDate><pubDate>Wed, 21 May 2008 14:12:58 GMT</pubDate><ttl>60</ttl><item><title>一个有意思的问题</title><link>http://www.cppblog.com/yunduan5158/archive/2005/11/11/1064.html</link><dc:creator>Merlin</dc:creator><author>Merlin</author><pubDate>Fri, 11 Nov 2005 04:56:00 GMT</pubDate><guid>http://www.cppblog.com/yunduan5158/archive/2005/11/11/1064.html</guid><wfw:comment>http://www.cppblog.com/yunduan5158/comments/1064.html</wfw:comment><comments>http://www.cppblog.com/yunduan5158/archive/2005/11/11/1064.html#Feedback</comments><slash:comments>15</slash:comments><wfw:commentRss>http://www.cppblog.com/yunduan5158/comments/commentRss/1064.html</wfw:commentRss><trackback:ping>http://www.cppblog.com/yunduan5158/services/trackbacks/1064.html</trackback:ping><description><![CDATA[<P>老师提出一个很有意思的问题：<BR></P>
<DIV style="BORDER-RIGHT: #cccccc 1px solid; PADDING-RIGHT: 5px; BORDER-TOP: #cccccc 1px solid; PADDING-LEFT: 4px; FONT-SIZE: 13px; PADDING-BOTTOM: 4px; BORDER-LEFT: #cccccc 1px solid; WIDTH: 98%; WORD-BREAK: break-all; PADDING-TOP: 4px; BORDER-BOTTOM: #cccccc 1px solid; BACKGROUND-COLOR: #eeeeee"><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top><SPAN style="COLOR: #0000ff">class</SPAN><SPAN style="COLOR: #000000">&nbsp;b<BR><IMG id=Codehighlighter1_8_55_Open_Image onclick="this.style.display='none'; Codehighlighter1_8_55_Open_Text.style.display='none'; Codehighlighter1_8_55_Closed_Image.style.display='inline'; Codehighlighter1_8_55_Closed_Text.style.display='inline';" src="http://www.cppblog.com/images/OutliningIndicators/ExpandedBlockStart.gif" align=top><IMG id=Codehighlighter1_8_55_Closed_Image style="DISPLAY: none" onclick="this.style.display='none'; Codehighlighter1_8_55_Closed_Text.style.display='none'; Codehighlighter1_8_55_Open_Image.style.display='inline'; Codehighlighter1_8_55_Open_Text.style.display='inline';" src="http://www.cppblog.com/images/OutliningIndicators/ContractedBlock.gif" align=top></SPAN><SPAN id=Codehighlighter1_8_55_Closed_Text style="BORDER-RIGHT: #808080 1px solid; BORDER-TOP: #808080 1px solid; DISPLAY: none; BORDER-LEFT: #808080 1px solid; BORDER-BOTTOM: #808080 1px solid; BACKGROUND-COLOR: #ffffff"><IMG src="http://www.cppblog.com/images/dot.gif"></SPAN><SPAN id=Codehighlighter1_8_55_Open_Text><SPAN style="COLOR: #000000">{<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>&nbsp;&nbsp;&nbsp;&nbsp;</SPAN><SPAN style="COLOR: #0000ff">char</SPAN><SPAN style="COLOR: #000000">&nbsp;c1;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>&nbsp;&nbsp;&nbsp;&nbsp;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>&nbsp;&nbsp;&nbsp;&nbsp;</SPAN><SPAN style="COLOR: #0000ff">long</SPAN><SPAN style="COLOR: #000000">&nbsp;l;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>&nbsp;&nbsp;&nbsp;&nbsp;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>&nbsp;&nbsp;&nbsp;&nbsp;</SPAN><SPAN style="COLOR: #0000ff">char</SPAN><SPAN style="COLOR: #000000">&nbsp;c2;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>&nbsp;&nbsp;&nbsp;&nbsp;</SPAN><SPAN style="COLOR: #0000ff">double</SPAN><SPAN style="COLOR: #000000">&nbsp;d;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top><BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/ExpandedBlockEnd.gif" align=top>}</SPAN></SPAN><SPAN style="COLOR: #000000">;</SPAN></DIV>与
<DIV style="BORDER-RIGHT: #cccccc 1px solid; PADDING-RIGHT: 5px; BORDER-TOP: #cccccc 1px solid; PADDING-LEFT: 4px; FONT-SIZE: 13px; PADDING-BOTTOM: 4px; BORDER-LEFT: #cccccc 1px solid; WIDTH: 98%; WORD-BREAK: break-all; PADDING-TOP: 4px; BORDER-BOTTOM: #cccccc 1px solid; BACKGROUND-COLOR: #eeeeee"><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top><SPAN style="COLOR: #0000ff">class</SPAN><SPAN style="COLOR: #000000">&nbsp;b<BR><IMG id=Codehighlighter1_8_62_Open_Image onclick="this.style.display='none'; Codehighlighter1_8_62_Open_Text.style.display='none'; Codehighlighter1_8_62_Closed_Image.style.display='inline'; Codehighlighter1_8_62_Closed_Text.style.display='inline';" src="http://www.cppblog.com/images/OutliningIndicators/ExpandedBlockStart.gif" align=top><IMG id=Codehighlighter1_8_62_Closed_Image style="DISPLAY: none" onclick="this.style.display='none'; Codehighlighter1_8_62_Closed_Text.style.display='none'; Codehighlighter1_8_62_Open_Image.style.display='inline'; Codehighlighter1_8_62_Open_Text.style.display='inline';" src="http://www.cppblog.com/images/OutliningIndicators/ContractedBlock.gif" align=top></SPAN><SPAN id=Codehighlighter1_8_62_Closed_Text style="BORDER-RIGHT: #808080 1px solid; BORDER-TOP: #808080 1px solid; DISPLAY: none; BORDER-LEFT: #808080 1px solid; BORDER-BOTTOM: #808080 1px solid; BACKGROUND-COLOR: #ffffff"><IMG src="http://www.cppblog.com/images/dot.gif"></SPAN><SPAN id=Codehighlighter1_8_62_Open_Text><SPAN style="COLOR: #000000">{<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>&nbsp;&nbsp;&nbsp;&nbsp;</SPAN><SPAN style="COLOR: #0000ff">char</SPAN><SPAN style="COLOR: #000000">&nbsp;c1;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>&nbsp;&nbsp;&nbsp;&nbsp;</SPAN><SPAN style="COLOR: #0000ff">char</SPAN><SPAN style="COLOR: #000000">&nbsp;c2;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top><BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</SPAN><SPAN style="COLOR: #0000ff">long</SPAN><SPAN style="COLOR: #000000">&nbsp;l;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>&nbsp;&nbsp;&nbsp;&nbsp;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>&nbsp;&nbsp;&nbsp;&nbsp;</SPAN><SPAN style="COLOR: #0000ff">double</SPAN><SPAN style="COLOR: #000000">&nbsp;d;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>&nbsp;&nbsp;&nbsp;&nbsp;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/ExpandedBlockEnd.gif" align=top>}</SPAN></SPAN><SPAN style="COLOR: #000000">;</SPAN></DIV>在存储的时候用的空间是不一样大的，前者是24，后者是16，为什么？<BR>-------------------------------------------------------------------------------------------------------------------------<BR>我在自己的机器上也运行了，的确如此，我知道16是怎么来的， char是2，long是4，double是8，2+2+4+8=16，而24我就太明白了，说地址是4字节的，char是2，要空两个字节，那第一个也应该是20阿，怎么会是24呢？有明白人的给讲讲！<img src ="http://www.cppblog.com/yunduan5158/aggbug/1064.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.cppblog.com/yunduan5158/" target="_blank">Merlin</a> 2005-11-11 12:56 <a href="http://www.cppblog.com/yunduan5158/archive/2005/11/11/1064.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>new</title><link>http://www.cppblog.com/yunduan5158/archive/2005/10/24/837.html</link><dc:creator>Merlin</dc:creator><author>Merlin</author><pubDate>Mon, 24 Oct 2005 14:26:00 GMT</pubDate><guid>http://www.cppblog.com/yunduan5158/archive/2005/10/24/837.html</guid><wfw:comment>http://www.cppblog.com/yunduan5158/comments/837.html</wfw:comment><comments>http://www.cppblog.com/yunduan5158/archive/2005/10/24/837.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.cppblog.com/yunduan5158/comments/commentRss/837.html</wfw:commentRss><trackback:ping>http://www.cppblog.com/yunduan5158/services/trackbacks/837.html</trackback:ping><description><![CDATA[<DIV class=O v:shape="_x0000_s1026">
<DIV style="mso-line-spacing: '150 20 0'; mso-margin-left-alt: 216; mso-char-wrap: 1; mso-kinsoku-overflow: 1"><SPAN style="FONT-FAMILY: 宋体; text-shadow: auto; mso-fareast-font-family: 宋体; mso-hansi-font-family: Arial">
<DIV style="BORDER-RIGHT: #cccccc 1px solid; PADDING-RIGHT: 5px; BORDER-TOP: #cccccc 1px solid; PADDING-LEFT: 4px; FONT-SIZE: 13px; PADDING-BOTTOM: 4px; BORDER-LEFT: #cccccc 1px solid; WIDTH: 98%; WORD-BREAK: break-all; PADDING-TOP: 4px; BORDER-BOTTOM: #cccccc 1px solid; BACKGROUND-COLOR: #eeeeee"><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top><SPAN style="COLOR: #008000">//</SPAN><SPAN style="COLOR: #008000">运算符new用于动态存储分配。 <BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top></SPAN><SPAN style="COLOR: #008000">//</SPAN><SPAN style="COLOR: #008000">new返回一个指向所分配空间的指针。<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top></SPAN><SPAN style="COLOR: #008000">//</SPAN><SPAN style="COLOR: #008000">例：</SPAN><SPAN style="COLOR: #008000"><BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top></SPAN><SPAN style="COLOR: #0000ff">int</SPAN><SPAN style="COLOR: #000000"> x；y</SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #0000ff">new</SPAN><SPAN style="COLOR: #000000"> </SPAN><SPAN style="COLOR: #0000ff">int</SPAN><SPAN style="COLOR: #000000">；y</SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #000000">10</SPAN><SPAN style="COLOR: #000000">；<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top></SPAN><SPAN style="COLOR: #008000">//</SPAN><SPAN style="COLOR: #008000">也可将上述各语句作适当合并如下：</SPAN><SPAN style="COLOR: #008000"><BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top></SPAN><SPAN style="COLOR: #0000ff">int</SPAN><SPAN style="COLOR: #000000"> y</SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #0000ff">new</SPAN><SPAN style="COLOR: #000000"> </SPAN><SPAN style="COLOR: #0000ff">int</SPAN><SPAN style="COLOR: #000000">；y</SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #000000">10</SPAN><SPAN style="COLOR: #000000">；<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top></SPAN><SPAN style="COLOR: #008000">//</SPAN><SPAN style="COLOR: #008000">或 int y=new int(10)；<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top></SPAN><SPAN style="COLOR: #008000">//</SPAN><SPAN style="COLOR: #008000">或 int y；y=new int(10)；</SPAN></DIV></SPAN></DIV></DIV><img src ="http://www.cppblog.com/yunduan5158/aggbug/837.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.cppblog.com/yunduan5158/" target="_blank">Merlin</a> 2005-10-24 22:26 <a href="http://www.cppblog.com/yunduan5158/archive/2005/10/24/837.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>strlen&amp;sizeof</title><link>http://www.cppblog.com/yunduan5158/archive/2005/10/21/785.html</link><dc:creator>Merlin</dc:creator><author>Merlin</author><pubDate>Fri, 21 Oct 2005 14:01:00 GMT</pubDate><guid>http://www.cppblog.com/yunduan5158/archive/2005/10/21/785.html</guid><wfw:comment>http://www.cppblog.com/yunduan5158/comments/785.html</wfw:comment><comments>http://www.cppblog.com/yunduan5158/archive/2005/10/21/785.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.cppblog.com/yunduan5158/comments/commentRss/785.html</wfw:commentRss><trackback:ping>http://www.cppblog.com/yunduan5158/services/trackbacks/785.html</trackback:ping><description><![CDATA[<P> </P>
<DIV style="BORDER-RIGHT: #cccccc 1px solid; PADDING-RIGHT: 5px; BORDER-TOP: #cccccc 1px solid; PADDING-LEFT: 4px; FONT-SIZE: 13px; PADDING-BOTTOM: 4px; BORDER-LEFT: #cccccc 1px solid; WIDTH: 98%; WORD-BREAK: break-all; PADDING-TOP: 4px; BORDER-BOTTOM: #cccccc 1px solid; BACKGROUND-COLOR: #eeeeee"><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top><SPAN style="COLOR: #000000">#include</SPAN><SPAN style="COLOR: #000000"><</SPAN><SPAN style="COLOR: #000000">iostream</SPAN><SPAN style="COLOR: #000000">></SPAN><SPAN style="COLOR: #000000"><BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top></SPAN><SPAN style="COLOR: #0000ff">using</SPAN><SPAN style="COLOR: #000000"> </SPAN><SPAN style="COLOR: #0000ff">namespace</SPAN><SPAN style="COLOR: #000000"> std;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/None.gif" align=top></SPAN><SPAN style="COLOR: #0000ff">int</SPAN><SPAN style="COLOR: #000000"> main()<BR><IMG id=Codehighlighter1_51_137_Open_Image onclick="this.style.display='none'; Codehighlighter1_51_137_Open_Text.style.display='none'; Codehighlighter1_51_137_Closed_Image.style.display='inline'; Codehighlighter1_51_137_Closed_Text.style.display='inline';" src="http://www.cppblog.com/images/OutliningIndicators/ExpandedBlockStart.gif" align=top><IMG id=Codehighlighter1_51_137_Closed_Image style="DISPLAY: none" onclick="this.style.display='none'; Codehighlighter1_51_137_Closed_Text.style.display='none'; Codehighlighter1_51_137_Open_Image.style.display='inline'; Codehighlighter1_51_137_Open_Text.style.display='inline';" src="http://www.cppblog.com/images/OutliningIndicators/ContractedBlock.gif" align=top></SPAN><SPAN id=Codehighlighter1_51_137_Closed_Text style="BORDER-RIGHT: #808080 1px solid; BORDER-TOP: #808080 1px solid; DISPLAY: none; BORDER-LEFT: #808080 1px solid; BORDER-BOTTOM: #808080 1px solid; BACKGROUND-COLOR: #ffffff"><IMG src="http://www.cppblog.com/images/dot.gif"></SPAN><SPAN id=Codehighlighter1_51_137_Open_Text><SPAN style="COLOR: #000000">{<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top></SPAN><SPAN style="COLOR: #0000ff">char</SPAN><SPAN style="COLOR: #000000"> test[</SPAN><SPAN style="COLOR: #000000">100</SPAN><SPAN style="COLOR: #000000">]</SPAN><SPAN style="COLOR: #000000">=</SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">asdfghjkl</SPAN><SPAN style="COLOR: #000000">"</SPAN><SPAN style="COLOR: #000000">;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top>cout</SPAN><SPAN style="COLOR: #000000"><<</SPAN><SPAN style="COLOR: #000000">strlen(you);</SPAN><SPAN style="COLOR: #008000">//</SPAN><SPAN style="COLOR: #008000">9</SPAN><SPAN style="COLOR: #008000"><BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top></SPAN><SPAN style="COLOR: #000000">cout</SPAN><SPAN style="COLOR: #000000"><<</SPAN><SPAN style="COLOR: #0000ff">sizeof</SPAN><SPAN style="COLOR: #000000">(you);</SPAN><SPAN style="COLOR: #008000">//</SPAN><SPAN style="COLOR: #008000">100</SPAN><SPAN style="COLOR: #008000"><BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/InBlock.gif" align=top></SPAN><SPAN style="COLOR: #0000ff">return</SPAN><SPAN style="COLOR: #000000"> </SPAN><SPAN style="COLOR: #000000">0</SPAN><SPAN style="COLOR: #000000">;<BR><IMG src="http://www.cppblog.com/images/OutliningIndicators/ExpandedBlockEnd.gif" align=top>}</SPAN></SPAN></DIV><img src ="http://www.cppblog.com/yunduan5158/aggbug/785.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.cppblog.com/yunduan5158/" target="_blank">Merlin</a> 2005-10-21 22:01 <a href="http://www.cppblog.com/yunduan5158/archive/2005/10/21/785.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item><item><title>近期目标</title><link>http://www.cppblog.com/yunduan5158/archive/2005/10/21/769.html</link><dc:creator>Merlin</dc:creator><author>Merlin</author><pubDate>Fri, 21 Oct 2005 04:52:00 GMT</pubDate><guid>http://www.cppblog.com/yunduan5158/archive/2005/10/21/769.html</guid><wfw:comment>http://www.cppblog.com/yunduan5158/comments/769.html</wfw:comment><comments>http://www.cppblog.com/yunduan5158/archive/2005/10/21/769.html#Feedback</comments><slash:comments>0</slash:comments><wfw:commentRss>http://www.cppblog.com/yunduan5158/comments/commentRss/769.html</wfw:commentRss><trackback:ping>http://www.cppblog.com/yunduan5158/services/trackbacks/769.html</trackback:ping><description><![CDATA[<P>终于有自己的博客了，一直想把自己刚学的东西或者是刚领悟到的东西记录下来，苦于没有地方，现在好了，我可以记录下来了。我学C++也有两年的时间了，不过还是一点突破也没有，还是有很多很简单的概念、问题不明白，我想在这个随笔里面，把它记录下来，并解决它。现在我还在学习一些算法，我想把他们也记录下来。</P><img src ="http://www.cppblog.com/yunduan5158/aggbug/769.html" width = "1" height = "1" /><br><br><div align=right><a style="text-decoration:none;" href="http://www.cppblog.com/yunduan5158/" target="_blank">Merlin</a> 2005-10-21 12:52 <a href="http://www.cppblog.com/yunduan5158/archive/2005/10/21/769.html#Feedback" target="_blank" style="text-decoration:none;">发表评论</a></div>]]></description></item></channel></rss>