Merge pull request TheAlgorithms#64 from KuLi/bucket_sort

ms10398 · web-flow · commit 7b82729d7ebe · 2018-10-23T10:49:45.000+05:30
Implemented bucket sort algorithm
diff --git a/Sorts/bucketSort.js b/Sorts/bucketSort.js
@@ -0,0 +1,62 @@
+/* 
+Wikipedia says: Bucket sort, or bin sort, is a sorting algorithm that works by distributing the
+elements of an array into a number of buckets. Each bucket is then sorted individually, either using
+a different sorting algorithm, or by recursively applying the bucket sorting algorithm. It is a
+distribution sort, and is a cousin of radix sort in the most to least significant digit flavour.
+Bucket sort is a generalization of pigeonhole sort. Bucket sort can be implemented with comparisons
+and therefore can also be considered a comparison sort algorithm. The computational complexity estimates
+involve the number of buckets.
+
+Time Complexity of Solution:
+Best Case O(n); Average Case O(n); Worst Case O(n)
+
+*/
+function bucketSort(list, size){
+    
+    if(undefined === size){
+        size = 5;
+    }
+    if(list.length === 0){
+        return list;
+    }
+    let min = list[0];
+    let max = list[0];
+    // find min and max
+    for(let iList = 0; iList < list.length; iList++){
+        
+        if(list[iList] < min){
+            min = list[iList];
+        } else if(list[iList] > max){
+            max = list[iList];
+        }
+    }
+    // how many buckets we need
+    let count = Math.floor((max - min) / size) + 1;
+
+    // create buckets
+    let buckets = [];
+    for(let iCount = 0; iCount < count; iCount++){
+        buckets.push([]);
+    }
+
+    // bucket fill
+    for(let iBucket = 0; iBucket < list.length; iBucket++){
+        let key = Math.floor((list[iBucket] - min) / size);
+        buckets[key].push(list[iBucket])
+    }
+    let sorted = [];
+    // now sort every bucket and merge it to the sorted list
+    for(let iBucket = 0; iBucket < buckets.length; iBucket++){
+        let arr = buckets[iBucket].sort();
+        for(let iSorted = 0; iSorted < arr.length; iSorted++){
+            sorted.push(arr[iSorted]);
+        }
+    }
+    return sorted;
+}
+let arrOrignal = [5, 6, 7, 8, 1, 2, 12, 14];
+//Array before Sort
+console.log(arrOrignal);
+arrSorted = bucketSort(arrOrignal);
+//Array after sort
+console.log(arrSorted); 
