Mergesort implementation complete.

index.html

@@ -115,7 +115,7 @@
         console.log('SHUFFLED: ' + b.join(','));
 
         var ordered = Object.create(shuffled);
-        MS.sort(ordered, 0, ordered.length - 1);
+        var ordered = MS.sort(ordered, 0, ordered.length - 1);
         var c = []
         ordered.forEach(function(obj0) {
             c.push(obj0.value);

js/mergesort.js

@@ -25,29 +25,54 @@ Mergesort.prototype.addInstruction = function(operation, left, right, mid) {
     });
 };
 
-var count = 0;
+var dump = function(arr) {
+    var d = [];
+    arr.forEach(function(obj) {
+        d.push(obj.value);
+    })
+
+    return d.join(',');
+}
 
 /**
  *
  */
 Mergesort.prototype.sort = function(arr, start, end) {
-    count++;
-
-    if (count > 30) {
-        console.error('count exceeded');
-        return;
-    }
-
-    if (start >= end) {
-        this.addInstruction('single', start, end, null);
-        return;
+    if (start === end) {
+        this.addInstruction('single', start);
+        return new Array(arr[start]);
     }
 
     var mid = start + Math.floor((end - start) / 2);
-    // this.addInstruction('init', start, end, mid);
 
+    var arr1 = this.sort(arr, start, mid);
+    var arr2 = this.sort(arr, mid + 1, end);
+
+    var result = this.merge(arr1, arr2);
+
+    return result;
+};
+
+/**
+ *
+ */
+Mergesort.prototype.merge = function(arr1, arr2) {
+    var result = [];
+
+    while (arr1.length > 0 || arr2.length > 0) {
+        if (arr1.length === 0) {
+            result.push(arr2.shift());
+        }
+        else if (arr2.length === 0) {
+            result.push(arr1.shift());
+        }
+        else if (arr1[0].value <= arr2[0].value) {
+            result.push(arr1.shift());
+        }
+        else {
+            result.push(arr2.shift());
+        }
+    }
 
-    this.sort(arr, start, mid);
-    this.sort(arr, mid + 1, end);
-    return;
+    return result;
 };