📄 page_1036.html
字号:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <title>page_1036</title> <link rel="stylesheet" href="reset.css" type="text/css" media="all"> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> </head> <body> <table summary="top nav" border="0" width="100%"> <tr> <td align="left" width="30%" style="background: #EEF3E2"><a style="color: blue; font-size: 120%; font-weight: bold; text-decoration: none; font-family: verdana;" href="page_1035.html">< previous page</a></td> <td align="center" width="40%" style="background: #EEF3E2"><strong style="color: #2F4F4F; font-size: 120%;">page_1036</strong></td> <td align="right" width="30%" style="background: #EEF3E2"><a style="color: blue; font-size: 120%; font-weight: bold; text-decoration: none; font-family: verdana;" href="page_1037.html">next page ></a></td> </tr> <tr> <td align="left" colspan="3" style="background: #ffffff; padding: 20px;"> <table border="0" width="100%" cellpadding="0"><tr><td align="center"> <table border="0" cellpadding="2" cellspacing="0" width="100%"><tr><td align="left"></td> <td align="right"></td> </tr></table></td></tr><tr><td align="left"><p></p><table border="0" cellspacing="0" cellpadding="0" width="100%"><tr><td align="right"><font face="Times New Roman, Times, Serif" size="2" color="#FF0000">Page 1036</font></td></tr></table><table border="0" cellspacing="0" cellpadding="0"><tr><td rowspan="5"></td> <td colspan="3" height="12"></td> <td rowspan="5"></td></tr><tr><td colspan="3"></td></tr><tr><td></td> <td><font face="Courier New, Courier, Mono New, Courier, Mono" size="2">3.聽a.聽recPtr聽=聽&oneRec;<br />聽聽聽b.聽(*recPtr).weight聽=聽120.5;<br />聽聽聽聽聽聽recPtr->weight聽=聽120.5;<br />4.聽a.聽double*聽dblPtr聽=聽new聽double;<br />聽聽聽聽聽聽*dblPtr聽=聽98.32586728;<br />聽聽聽b.聽int*聽list聽=聽new聽int[50];<br />聽聽聽聽聽聽for聽(i聽=聽0;聽i聽<聽50;聽i++)<br />聽聽聽聽聽聽聽聽聽聽聽list[i]聽=聽0;<br />5.聽delete聽dblPtr;<br />聽聽聽delete聽[]聽list;</font></td><td></td></tr><tr><td colspan="3"></td></tr><tr><td colspan="3" height="1"></td></tr></table><table border="0" cellspacing="0" cellpadding="0"><tr><td rowspan="5"></td> <td colspan="3" height="12"></td> <td rowspan="5"></td></tr><tr><td colspan="3"></td></tr><tr><td></td> <td><font face="Times New Roman, Times, Serif" size="3">6. </font><font face="Courier New, Courier, Mono New, Courier, Mono" size="3">float&聽gamma聽=聽delta;</font><font face="Times New Roman, Times, Serif" size="3"> 7. </font><font face="Courier New, Courier, Mono New, Courier, Mono" size="3">gamma聽=聽12.9;</font><font face="Times New Roman, Times, Serif" size="3"> (Remember that once a reference variable is initialized, each appearance of the variable is <i>implicitly</i> dereferenced.) 8. Shallow copying copies one pointer to another without copying any pointed-to data. 9. (a.) Passing a class object as a parameter using pass-by-value. (b.) Initializing a class object in its declaration. (c.) Returning a class object as a function value. 10. The class needs one or more constructors (to create the dynamic data), a destructor (to clean up the free store), a deep copy operation, and a copy-constructor (for deep copying during initializations). 11. Pointers, when used with dynamic data, improve memory efficiency because we create only as many dynamic variables as are needed. With respect to time efficiency, it is faster to move pointers than to move large data structures, as in the case of sorting large </font><font face="Courier New, Courier, Mono New, Courier, Mono" size="3">structs</font><font face="Times New Roman, Times, Serif" size="3">.</font></td><td></td></tr><tr><td colspan="3"></td></tr><tr><td colspan="3" height="1"></td></tr></table><table border="0" cellspacing="0" cellpadding="0"><tr><td rowspan="5"></td> <td colspan="3" height="12"></td> <td rowspan="5"></td></tr><tr><td colspan="3"></td></tr><tr><td></td> <td><font face="Times New Roman, Times, Serif" size="3"><i>Exam Preparation Exercises</i></font></td><td></td></tr><tr><td colspan="3"></td></tr><tr><td colspan="3" height="1"></td></tr></table><table border="0" cellspacing="0" cellpadding="0"><tr><td rowspan="5"></td> <td colspan="3" height="12"></td> <td rowspan="5"></td></tr><tr><td colspan="3"></td></tr><tr><td></td> <td><font face="Times New Roman, Times, Serif" size="3">1. How does a variable of type </font><font face="Courier New, Courier, Mono New, Courier, Mono" size="3">float*</font><font face="Times New Roman, Times, Serif" size="3"> differ from a variable of type </font><font face="Courier New, Courier, Mono New, Courier, Mono" size="3">float</font><font face="Times New Roman, Times, Serif" size="3">?</font></td><td></td></tr><tr><td colspan="3"></td></tr><tr><td colspan="3" height="1"></td></tr></table><table border="0" cellspacing="0" cellpadding="0"><tr><td rowspan="5"></td> <td colspan="3" height="12"></td> <td rowspan="5"></td></tr><tr><td colspan="3"></td></tr><tr><td></td> <td><font face="Times New Roman, Times, Serif" size="3">2. Show what is output by the following C++ code. If an unknown value gets printed, write a <i>U.</i></font></td><td></td></tr><tr><td colspan="3"></td></tr><tr><td colspan="3" height="1"></td></tr></table><table border="0" cellspacing="0" cellpadding="0"><tr><td rowspan="5"><img src="3e26ecb1b6ac508ae10a0e39d2fb98b2.gif" border="0" width="24" height="1" alt="3e26ecb1b6ac508ae10a0e39d2fb98b2.gif" /></td> <td colspan="3" height="12"></td> <td rowspan="5"></td></tr><tr><td colspan="3"></td></tr><tr><td></td> <td><font face="Courier New, Courier, Mono New, Courier, Mono" size="2">int聽main()<br />{<br />聽聽聽聽int聽m;<br />聽聽聽聽int聽n;<br />聽聽聽聽int*聽p聽=聽&m;<br />聽聽聽聽int*聽q;<br /><br />聽聽聽聽*p聽=聽27;<br />聽聽聽聽cout聽<聽*p聽<聽聽聽<聽*q聽<聽endl;<br />聽聽聽聽q聽=聽&n;<br />聽聽聽聽n聽=聽54;<br />聽聽聽聽cout聽<聽*p聽<聽聽聽<聽*q聽<聽endl;<br />聽聽聽聽p聽=聽&n;<br />聽聽聽聽*p聽=聽6;<br />聽聽聽聽cout聽<聽*p聽<聽聽聽<聽n聽<聽endl;<br />聽聽聽聽return聽0;<br />}</font></td><td></td></tr><tr><td colspan="3"></td></tr><tr><td colspan="3" height="1"></td></tr></table><table border="0" cellspacing="0" cellpadding="0"><tr><td rowspan="5"></td> <td colspan="3" height="12"></td> <td rowspan="5"></td></tr><tr><td colspan="3"></td></tr><tr><td></td> <td><font face="Times New Roman, Times, Serif" size="3">3. Given the declarations</font></td><td></td></tr><tr><td colspan="3"></td></tr><tr><td colspan="3" height="1"></td></tr></table><table border="0" cellspacing="0" cellpadding="0"><tr><td rowspan="5"><img src="3e26ecb1b6ac508ae10a0e39d2fb98b2.gif" border="0" width="24" height="1" alt="3e26ecb1b6ac508ae10a0e39d2fb98b2.gif" /></td> <td colspan="3" height="12"></td> <td rowspan="5"></td></tr><tr><td colspan="3"></td></tr><tr><td></td> <td><font face="Courier New, Courier, Mono New, Courier, Mono" size="2">struct聽PersonType<br />{<br />聽聽聽聽char聽lastName[31];<br />聽聽聽聽char聽firstnitial;<br />};<br /></font></td><td></td></tr><tr><td colspan="3"></td></tr><tr><td colspan="3" height="1"></td></tr></table></td></tr></table><p><font size="0"></font></p>聽 </td> </tr> <tr> <td align="left" width="30%" style="background: #EEF3E2"><a style="color: blue; font-size: 120%; font-weight: bold; text-decoration: none; font-family: verdana;" href="page_1035.html">< previous page</a></td> <td align="center" width="40%" style="background: #EEF3E2"><strong style="color: #2F4F4F; font-size: 120%;">page_1036</strong></td> <td align="right" width="30%" style="background: #EEF3E2"><a style="color: blue; font-size: 120%; font-weight: bold; text-decoration: none; font-family: verdana;" href="page_1037.html">next page ></a></td> </tr> </table> </body> </html>⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -