From a2dd6ac325c47fbc306d34528512edb49642166f Mon Sep 17 00:00:00 2001
From: finnm <finn.moltmann@tu-dortmund.de>
Date: Tue, 17 Dec 2024 17:55:36 +0100
Subject: [PATCH] Handling of descending runs

---
 .../powersort/FinnSort/FinnSort.java          | 35 ++++++++++++++++---
 1 file changed, 30 insertions(+), 5 deletions(-)

diff --git a/app/src/main/java/de/uni_marburg/powersort/FinnSort/FinnSort.java b/app/src/main/java/de/uni_marburg/powersort/FinnSort/FinnSort.java
index ae5f1c5..657e532 100644
--- a/app/src/main/java/de/uni_marburg/powersort/FinnSort/FinnSort.java
+++ b/app/src/main/java/de/uni_marburg/powersort/FinnSort/FinnSort.java
@@ -15,7 +15,7 @@ public class FinnSort {
         int i = 0;
         int j = extendRunRight(a, i, c);
 
-//        printList(a, c);
+        //printList(a, c);
 
         runs.add(new Run(i, j, 0));
 
@@ -63,17 +63,40 @@ public class FinnSort {
         System.arraycopy(merge.toArray(), 0, a, min(r1.start, r2.start), merge.size());
         Run r = new Run(min(r1.start, r2.start), max(r1.end, r2.end), min(r1.power, r2.power));
         runs.add(r);
-//        printList(a, c);
+        //printList(a, c);
     }
 
     private static <T> int extendRunRight(T[] a, int i, Comparator<? super T> c) {
+        if (i >= a.length - 1)
+            return i + 1;
+
+
         int j = i + 1;
-        while (j < a.length && c.compare(a[j-1], a[j]) <= 0) {
-            j++;
+        if (c.compare(a[i], a[j]) < 0) { //
+            while (j < a.length && c.compare(a[j - 1], a[j]) <= 0) {
+                j++;
+            }
+        } else {
+            while (j < a.length && c.compare(a[j - 1], a[j]) >= 0) {
+                j++;
+            }
+            makeAscending(a, i, j);
         }
         return j;
     }
 
+    private static <T> void makeAscending(T[] a, int i, int j) {
+        for (int p = 0; p < (j - i) / 2; p++)  {
+            swap(a, i + p ,j - p - 1);
+        }
+    }
+
+    private static <T> void swap(T[] a, int i, int j) {
+        T temp = a[i];
+        a[i] = a[j];
+        a[j] = temp;
+    }
+
     private static int power(Run run1, Run run2, int n) {
         if (run1.start == 0) {
             return 0;
@@ -89,7 +112,7 @@ public class FinnSort {
         }
         return l;
     }
-
+/*
     public static void printRuns() {
         String s = "";
         for (Run run : runs) {
@@ -111,4 +134,6 @@ public class FinnSort {
         }
         System.out.println(s);
     }
+
+ */
 }
\ No newline at end of file