bugfixes + new sorting algorithm

Author: MattMoony

algos/intro_sort.js

@@ -1,5 +1,5 @@
 async function introSort(a, display) {
-    let maxDepth = Math.floor(Math.log(a.length) * 2)
+    let maxDepth = Math.floor(Math.log(a.length) * 2);
     await introSort_rec(a, 0, a.length-1, maxDepth, display);
 }
 
@@ -20,7 +20,7 @@ async function introSort_rec(a, l, r, maxd, display) {
         }
     }
     else {
-        if (p-l >= 1) {
+        if ((p-1)-l >= 1) {
             await introSort_rec(a, l, p-1, maxd-1, display);
         }
         if (r-(p+1) >= 1) {

algos/merge_sort.js

@@ -16,10 +16,10 @@ async function mergeSort(a, l, r, display) {
     while (a2[0] !== undefined) {
         if (a1[0] < a2[0]) {
             a3[i] = a1.splice(0, 1)[0];
-            a[i] = a3[i];
+            a[i+l] = a3[i];
         } else {
             a3[i] = a2.splice(0, 1)[0];
-            a[i] = a3[i];
+            a[i+l] = a3[i];
         }
 
         glob_comp += 2;
@@ -37,7 +37,7 @@ async function mergeSort(a, l, r, display) {
     a3.push(...a2);
 
     for (let j = i; j < a3.length; j++) {
-        a[j] = a3[j];
+        a[j+l] = a3[j];
     }
 
     display(a);

algos/quick_merge_sort.js

@@ -0,0 +1,13 @@
+async function qmSort(a, l, r, threshold, display) {
+    if (r-l<=threshold) {
+        await mergeSort(a, l, r, display);
+        return;
+    }
+
+    let p = await quickPartition(a, l, r, display);
+
+    if ((p-1)-l >= 1)
+        await qmSort(a, l, p-1, threshold, display);
+    if (r-(p+1) >= 1)
+        await qmSort(a, p+1, r, threshold, display);
+}

index.html

@@ -166,6 +166,7 @@ <h1><span class='important_letter'>S</span>orting <span class='important_letter'
                     <option value="shell_sort">ShellSort</option>
                     <option value="comb_sort">CombSort</option>
 
+                    <option value="quick_merge_sort">Quick-MergeSort</option>
                     <option value="gnome_sort">GnomeSort</option>
                     <option value="cocktail_sort">CocktailShaker-Sort</option>
                     <option value="cocktail_merge_sort">Cocktail-MergeSort</option>
@@ -250,6 +251,7 @@ <h1><span class='important_letter'>S</span>orting <span class='important_letter'
     <script src="algos/double_selection_sort.js"></script>
     <script src="algos/gravity_sort.js"></script>
     <script src="algos/cocktail_merge.js"></script>
+    <script src="algos/quick_merge_sort.js"></script>
 
     <script src="visualize.js"></script>
 
@@ -480,6 +482,13 @@ <h1><span class='important_letter'>S</span>orting <span class='important_letter'
                             doCocktailMergeSort(rarr);
                         }
                         break;
+                    case 'quick_merge_sort':
+                        {
+                            refresh(0, 0);
+                            rarr = glob_random_func(glob_amount, glob_upper, glob_lower, glob_display_func);
+                            doQuickMergeSort(rarr);
+                        }
+                        break;
                 }
             };
 

visualize.js

@@ -453,6 +453,21 @@ async function doCocktailMergeSort(rarr) {
 
     document.getElementById('algorithm_settings').style.display = "block";
 }
+async function doQuickMergeSort(rarr) {
+    document.getElementById('algorithm_settings').style.display = "none";
+
+    glob_comp = 0;
+    glob_movm = 0;
+
+    // -- QUICK-MERGE SORT -- //
+    document.getElementById('algorithm_div').innerHTML = "Quick-MergeSort";
+    await qmSort(rarr, 0, rarr.length-1, Math.floor(rarr.length/8), glob_display_func);
+
+    glob_comp = 0;
+    glob_movm = 0;
+
+    document.getElementById('algorithm_settings').style.display = "block";
+}
 
 
 async function visualize_init(amount, upper, lower) {