桶排序

php/13_sort/bucketSort.php

@@ -0,0 +1,50 @@
+<?php
+
+require_once '../12_sort/quickSort.php';
+
+
+$numbers = [11,23,45,67,88,99,22,34,56,78,90,12,34,5,6,91,92,93,93,94,95,94,95,96,97,98,99,100];
+$size = 10;
+var_dump(bucketSort($numbers,10));//加在了quickSort文件，请忽略前几个打印
+
+
+/**
+ * 桶排序
+ * 假设一个桶只能放置10个元素
+ * 当一个桶内元素过多，需要继续分桶
+ * @param array $numbers
+ * @param [type] $size
+ *
+ * @return void
+ * @date 2018/11/25
+ * @author yuanliandu 
+ */
+function bucketSort(array $numbers) {
+    $min = min($numbers);
+    $max = max($numbers);
+    $length = count($numbers);
+    $bucketNumber =  ceil(($max-$min)/$length) + 1;
+    $buckets = [];
+    foreach($numbers as $key => $value) {
+        $index = ceil(($value-$min)/$length);
+        $buckets[$index][] = $value; 
+    }
+
+    $result = [];
+    for($i=0;$i<$bucketNumber;$i++) {
+        $bucket = $buckets[$i];
+        $length = count($bucket);
+        //如果桶内元素为空，跳过这个桶
+        if($length == 0) {
+            continue;
+        }
+        if( $length > 10) {
+            $bucket = bucketSort($bucket,$length);
+        }
+
+       quickSort($bucket,0,count($bucket)-1);
+       $result = array_merge($result,$bucket);
+   }
+   return $result;
+}
+