时间:2021-07-01 10:21:17 帮助过:5人阅读
- <br><!--?php <BR-->/** <br>* 查找 <br>* <br>**/ <br>// 顺序查找 <br>function normal_search($arrData,$val) { <br>$len = count($arrData); <br>if($len == 0) return -1; <br>for($i = 0;$i < $len; $i++ ) { <br>echo "find No.",$i + 1," value = ",$arrData[$i]," is = ",$val,"? <br>"; <br>// 找到了 <br>if($arrData[$i] == $val) return $i; <br>} <br>return -1; <br>} <br><br>// 测试顺序查找 <br>$arrData = array(4,51,6,73,2,5,9,33,50,3,4,6,1,4,67); <br>echo normal_search($arrData,6),"<br>"; <br>echo normal_search($arrData,66),"<br>"; <br><br>// 二分法查找(针对有序的列进行查找) <br>function binary_search($arrData,$val) { <br>$len = count($arrData); <br>if($len == 0) return -1; <br><br>$start = 0; <br>$end = $len - 1; <br><br>while($start <= $end) { <br>$middle = intval(($start + $end)/2); <br>echo "start = ",$start," end = ",$end," middle = ",$middle,"<br>"; <br>if($arrData[$middle] == $val) { <br>return $middle; <br>} elseif ($arrData[$middle] > $val) { <br>$end = $middle - 1 ; <br>} elseif ($arrData[$middle] < $val) { <br>$start = $middle + 1; <br>} <br>} <br>return -1; <br>} <br><br>// 测试一下二分法查找 <br>$arrData = array(1,2,3,4,5,7,8,9,11,23,56,100,104,578,1000); <br>echo binary_search($arrData,578),"<br>"; <br>echo binary_search($arrData,66),"<br>"; <br>
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- <p align="left"><span id="url" itemprop="url">http://www.bkjia.com/PHPjc/325529.html</span><span id="indexUrl" itemprop="indexUrl">www.bkjia.com</span><span id="isOriginal" itemprop="isOriginal">true</span><span id="isBasedOnUrl" itemprop="isBasedOnUrl">http://www.bkjia.com/PHPjc/325529.html</span><span id="genre" itemprop="genre">TechArticle</span><span id="description" itemprop="description"> 代码如下:</span></p><pre class="brush:php;toolbar:false layui-box layui-code-view layui-code-notepad"><ol class="layui-code-ol"><li>?php /** * 查找 * **/ // 顺序查找 function normal_search($arrData,$val) { $len = count($arrData); if($len == 0) return -1; for($i = 0;$i $len; $i++...<p></p></li><li> </li></ol></pre>