added PigeonHoleSort algorithm

Sorts/PigeonHoleSort.js

@@ -0,0 +1,41 @@
+/*
+*Pigeonhole sorting is a sorting algorithm that is suitable
+* for sorting lists of elements where the number of elements
+* (n) and the length of the range of possible key values (N)
+* are approximately the same.
+ */
+function pigeonhole_sort(arr){
+    var min = arr[0];
+    var max = arr[0];
+
+    for(let i=0; i<arr.length; i++)
+    {
+        if(arr[i] > max)
+            max = arr[i];
+        if(arr[i] < min)
+            min = arr[i];
+    }
+    console.log(max);
+    console.log(min);
+
+    var range = max - min + 1;
+    let pigeonhole = Array(range).fill(0);
+
+    for(let i = 0; i<arr.length; i++){
+        pigeonhole[arr[i] - min]++;
+    }
+
+    let index = 0;
+
+    for(let j = 0; j<range; j++){
+        while(pigeonhole[j]-->0){
+            arr[index++]=j+min;
+        }
+
+    }
+}
+//Driver code
+var arr=Array(8, 3, 2, 7, 4, 6, 8);
+pigeonhole_sort(arr);
+console.log(arr);
+