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<div id="Layer1" style="position:absolute; width:711px; height:21px; z-index:1; top: 10px; background-color: #CCCCCC; layer-background-color: #CCCCCC; border: 1px none #000000; left: 26px"><b>|</b><font face="宋体" size="2"><a href="../text1/text1-0.htm">第一章</a></font><b>|</b><font face="宋体" size="2"><a href="../text2/text2-0.htm">第二章</a></font><b>|</b><font face="宋体" size="2"><a href="../text3/text3-0.htm">第三章</a></font><b>|</b><font face="宋体" size="2"><a href="../text4/text4-0.htm">第四章</a></font><b>|</b><font face="宋体" size="2"><a href="../text5/text5-0.htm">第五章</a></font><b>|</b><font face="宋体" size="2"><a href="../text6/text6-0.htm">第六章</a></font><b>|</b><font face="宋体" size="2">第七章</font><b>|</b><font face="宋体" size="2"><a href="../text8/text8-0.htm">第八章</a></font><b>|</b><font face="宋体" size="2"><a href="../text9/text9-0.htm">第九章</a></font><b>|</b><font face="宋体" size="2"><a href="../text10/text10-0.htm">第十章</a></font><b>|</b><font size="2" face="宋体"><a href="../textA/textA-0.htm">算法分析</a><b><font color="#000000">|</font></b>
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<pre align="left"><font face="Arial, Helvetica, sans-serif" size="4" color="#000000"><b>
</b></font><b><font face="Arial, Helvetica, sans-serif" size="4" color="#000000"><font color="#FF0000"><i>t<font size="2">s</font></i></font><i><font face="Arial, Helvetica, sans-serif" size="4"> </font></i> =<i> maximum seek time</i>
<i><font color="#FF0000">t<font size="2">l</font> </font></i>= <i>maximum latency time</i>
<font color="#FF0000"><i>t<font size="2">rw</font></i></font><i><font face="Arial, Helvetica, sans-serif" size="4"> </font></i>=<i> time to read or write one block of 250 records</i>
<font color="#FF0000"><i>t<font size="2">IO</font></i></font><font size="2"><i><font face="Arial, Helvetica, sans-serif"> </font></i></font>= <i>t<font size="2">s</font> + t<font size="2">l</font> + t<font size="2">rw</font></i>
<font color="#FF0000"><i>t<font size="2">IS </font></i></font> = time to internally sort 750 records
<font color="#FF0000"><i>nt<font size="2">m</font> </i></font>= time to merge n records from input buffer to the output
buffer</font></b>
<b><font face="Arial, Helvetica, sans-serif" size="4" color="#000000"> <font color="#FF0000">operation </font> <font color="#FF0000">time </font>
(1) read 18 blocks of input , 18<font color="#0033CC"><i>t<font size="2">IO</font><font face="Arial, Helvetica, sans-serif" size="4"> </font></i></font> , 36<font color="#0033CC"><i>t<font size="2">IO</font></i></font> + 6 <font color="#0033CC"><i><font face="Arial, Helvetica, sans-serif" size="4">t<font size="2">IS</font></font></i></font><font size="2"></font>
internally sort, 6<font color="#0033CC"><i><font face="Arial, Helvetica, sans-serif" size="4">t<font size="2">IS</font> </font></i></font> ,
write 18 blocks, 18<font color="#0033CC"><i>t<font size="2">IO</font><font face="Arial, Helvetica, sans-serif" size="4"> </font></i></font>
(2) merge runs 1-6 in pairs 36 <font color="#0033CC"><i>t<font size="2">IO</font></i></font> + 4500 <i><font color="#0033CC">t<font size="2">m</font></font></i>
(3) merge two runs of 1500 records 24<font color="#0033CC"><i>t<font size="2">IO</font></i></font> + 3000 <i><font color="#0033CC">t<font size="2">m</font></font></i>
each , 12 blocks
(4) merge one run of 3000 records 36 <font color="#0033CC"><i>t<font size="2">IO</font></i></font>+ 4500 <i><font color="#0033CC">t<font size="2">m</font></font></i>
with one run of 1500 records ___________________
<font color="#FF0000"> total time </font> <font color="#0033CC"><i> 132t<font size="2">IO</font><font face="Arial, Helvetica, sans-serif" size="4"> + 12000 t<font size="2">m </font>+ 6t<font size="2">IS</font> </font> </i></font>
</font></b></pre>
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