c++常见问题答案.htm

面试题 希望对大家有所帮助 成功走向程序员之路

                  style="FONT-FAMILY: 宋体">{<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体"><SPAN>&nbsp;&nbsp;&nbsp; </SPAN>for 
                  (i=0; i&lt;N; i++)<O:P></O:P></SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 10.9pt"><SPAN 
                  lang=EN-US style="FONT-FAMILY: 宋体"><SPAN>&nbsp;&nbsp;&nbsp; 
                  </SPAN>DoOtherthing();<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体">}<O:P></O:P></SPAN></P></TD></TR>
              <TR style="HEIGHT: 59.6pt">
                <TD 
                style="BORDER-RIGHT: 1pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: 1pt solid; WIDTH: 201.35pt; PADDING-TOP: 0cm; BORDER-BOTTOM: 1pt solid; HEIGHT: 59.6pt" 
                vAlign=top width=268>
                  <P class=MsoNormal><SPAN style="FONT-FAMILY: 宋体">优点：<SPAN 
                  lang=EN-US><O:P></O:P></SPAN></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></P>
                  <P class=MsoNormal><SPAN style="FONT-FAMILY: 宋体">缺点：<SPAN 
                  lang=EN-US><O:P></O:P></SPAN></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></P></TD>
                <TD 
                style="BORDER-RIGHT: 1pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 212.4pt; PADDING-TOP: 0cm; BORDER-BOTTOM: 1pt solid; HEIGHT: 59.6pt" 
                vAlign=top width=283>
                  <P class=MsoNormal><SPAN style="FONT-FAMILY: 宋体">优点：<SPAN 
                  lang=EN-US><O:P></O:P></SPAN></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></P>
                  <P class=MsoNormal><SPAN style="FONT-FAMILY: 宋体">缺点：<SPAN 
                  lang=EN-US><O:P></O:P></SPAN></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></P></TD></TR></TBODY></TABLE>
            <P class=MsoNormal><SPAN lang=EN-US 
            style="FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></P>
            <TABLE class=MsoNormalTable 
            style="BORDER-RIGHT: medium none; BORDER-TOP: medium none; MARGIN-LEFT: 11pt; BORDER-LEFT: medium none; BORDER-BOTTOM: medium none; BORDER-COLLAPSE: collapse" 
            cellSpacing=0 cellPadding=0 border=1>
              <TBODY>
              <TR style="HEIGHT: 59.6pt">
                <TD 
                style="BORDER-RIGHT: windowtext 1pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 1pt solid; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: windowtext 1pt solid; WIDTH: 201.35pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 59.6pt" 
                vAlign=top width=268>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体">for (i=0; i&lt;N; 
                  i++)<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体">{<O:P></O:P></SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 10.9pt"><SPAN 
                  lang=EN-US style="COLOR: blue; FONT-FAMILY: 宋体">if 
                  (condition)<O:P></O:P></SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 10.9pt"><SPAN 
                  lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体"><SPAN>&nbsp;&nbsp;&nbsp; 
                  </SPAN>DoSomething();<O:P></O:P></SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 10.9pt"><SPAN 
                  lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体">else<O:P></O:P></SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 10.9pt"><SPAN 
                  lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体"><SPAN>&nbsp;&nbsp;&nbsp; 
                  </SPAN>DoOtherthing();<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体">}<O:P></O:P></SPAN></P></TD>
                <TD 
                style="BORDER-RIGHT: windowtext 1pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 1pt solid; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 212.4pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1pt solid; HEIGHT: 59.6pt" 
                vAlign=top width=283>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体">if 
                  (condition)<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体">{<O:P></O:P></SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 21.8pt"><SPAN 
                  lang=EN-US style="COLOR: blue; FONT-FAMILY: 宋体">for (i=0; 
                  i&lt;N; i++)<O:P></O:P></SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 10.9pt"><SPAN 
                  lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体"><SPAN>&nbsp;&nbsp;&nbsp; 
                  </SPAN>DoSomething();<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体">}<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体">else<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体">{<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体"><SPAN>&nbsp;&nbsp;&nbsp; 
                  </SPAN>for (i=0; i&lt;N; i++)<O:P></O:P></SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 10.9pt"><SPAN 
                  lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体"><SPAN>&nbsp;&nbsp;&nbsp; 
                  </SPAN>DoOtherthing();<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体">}<O:P></O:P></SPAN></P></TD></TR>
              <TR style="HEIGHT: 59.6pt">
                <TD 
                style="BORDER-RIGHT: 1pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: 1pt solid; WIDTH: 201.35pt; PADDING-TOP: 0cm; BORDER-BOTTOM: 1pt solid; HEIGHT: 59.6pt" 
                vAlign=top width=268>
                  <P class=MsoNormal><STRONG><SPAN 
                  style="COLOR: blue; FONT-FAMILY: 宋体">优点：程序简洁<SPAN 
                  lang=EN-US><O:P></O:P></SPAN></SPAN></STRONG></P>
                  <P class=MsoNormal><STRONG><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></STRONG></P>
                  <P class=MsoNormal><STRONG><SPAN 
                  style="COLOR: blue; FONT-FAMILY: 宋体">缺点：多执行了<SPAN 
                  lang=EN-US>N-1</SPAN>次逻辑判断，并且打断了循环“流水线”作业，使得编译器不能对循环进行优化处理，降低了效率。<SPAN 
                  lang=EN-US><O:P></O:P></SPAN></SPAN></STRONG></P></TD>
                <TD 
                style="BORDER-RIGHT: 1pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: medium none; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: medium none; WIDTH: 212.4pt; PADDING-TOP: 0cm; BORDER-BOTTOM: 1pt solid; HEIGHT: 59.6pt" 
                vAlign=top width=283>
                  <P class=MsoNormal><STRONG><SPAN 
                  style="COLOR: blue; FONT-FAMILY: 宋体">优点：循环的效率高<SPAN 
                  lang=EN-US><O:P></O:P></SPAN></SPAN></STRONG></P>
                  <P class=MsoNormal><STRONG><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></STRONG></P>
                  <P class=MsoNormal><STRONG><SPAN 
                  style="COLOR: blue; FONT-FAMILY: 宋体">缺点：程序不简洁<SPAN 
                  lang=EN-US><O:P></O:P></SPAN></SPAN></STRONG></P>
                  <P class=MsoNormal><STRONG><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></STRONG></P>
                  <P class=MsoNormal><STRONG><SPAN lang=EN-US 
                  style="COLOR: blue; FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></STRONG></P></TD></TR></TBODY></TABLE>
            <P class=MsoNormal><SPAN lang=EN-US><O:P>&nbsp;</O:P></SPAN></P>
            <P class=MsoNormal><SPAN lang=EN-US><O:P>&nbsp;</O:P></SPAN></P>
            <P class=MsoNormal><STRONG><SPAN 
            style="FONT-FAMILY: 宋体">有关内存的思考题（</SPAN><SPAN 
            lang=EN-US>20</SPAN></STRONG><STRONG><SPAN 
            style="FONT-FAMILY: 宋体">分）</SPAN><SPAN 
            lang=EN-US><O:P></O:P></SPAN></STRONG></P>
            <P class=MsoNormal><STRONG><SPAN 
            lang=EN-US><O:P>&nbsp;</O:P></SPAN></STRONG></P>
            <TABLE class=MsoNormalTable 
            style="BORDER-RIGHT: medium none; BORDER-TOP: medium none; BORDER-LEFT: medium none; BORDER-BOTTOM: medium none; BORDER-COLLAPSE: collapse" 
            cellSpacing=0 cellPadding=0 border=1>
              <TBODY>
              <TR>
                <TD 
                style="BORDER-RIGHT: windowtext 1pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 1pt solid; PADDING-LEFT: 5.4pt; PADDING-BOTTOM: 0cm; BORDER-LEFT: windowtext 1pt solid; WIDTH: 218pt; PADDING-TOP: 0cm; BORDER-BOTTOM: windowtext 1pt solid" 
                vAlign=top width=291>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体">void GetMemory(char 
                  *p)<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体">{<O:P></O:P></SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 10.5pt"><SPAN 
                  lang=EN-US style="FONT-FAMILY: 宋体">p = (char 
                  *)malloc(100);<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体">}<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US>void Test(void) 
</SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US>{</SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 10.5pt"><SPAN 
                  lang=EN-US style="FONT-FAMILY: 宋体">char *str = 
                  NULL;<O:P></O:P></SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 10.5pt"><SPAN 
                  lang=EN-US 
                  style="FONT-FAMILY: 宋体">GetMemory(str);<SPAN>&nbsp;&nbsp; 
                  </SPAN><O:P></O:P></SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 10.5pt"><SPAN 
                  lang=EN-US style="FONT-FAMILY: 宋体">strcpy(str, "hello 
                  world");<O:P></O:P></SPAN></P>
                  <P class=MsoNormal style="TEXT-INDENT: 10.5pt"><SPAN 
                  lang=EN-US 
                  style="FONT-FAMILY: 宋体">printf(str);<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体">}<O:P></O:P></SPAN></P>
                  <P class=MsoNormal><SPAN lang=EN-US 
                  style="FONT-FAMILY: 宋体"><O:P>&nbsp;</O:P></SPAN></P>
                  <P class=MsoNormal><SPAN style="FONT-FAMILY: 宋体">请问运行<SPAN 
                  lang=EN-US>Test</SPAN>函数会有什么样的结果？<SPAN 
                  lang=EN-US><O:P></O:P></SPAN></SPAN></P>
                  <P class=MsoNormal><SPAN style="FONT-FAMILY: 宋体">答：</SPAN></P>
                  <P class=MsoNormal><SPAN 
                  lang=EN-US><O:P>&nbsp;</O:P></SPAN></P>
                  <P class=MsoNormal><SPAN 
                  lang=EN-US><O:P>&nbsp;</O:P></SPAN></P>
                  <P class=MsoNormal><SPAN 
                  lang=EN-US><O:P>&nbsp;</O:P></SPAN></P>
                  <P class=MsoNormal><SPAN 
                  lang=EN-US><O:P>&nbsp;</O:P></SPAN></P></TD>
                <TD 
                style="BORDER-RIGHT: windowtext 1pt solid; PADDING-RIGHT: 5.4pt; BORDER-TOP: windowtext 1pt solid; PADD