Data update

Task/Sorting-algorithms-Merge-sort/SETL/sorting-algorithms-merge-sort.setl

@@ -0,0 +1,31 @@
+program merge_sort;
+    test := [-8, 241, 9, 316, -6, 3, 413, 9, 10];
+    print(test, '=>', mergesort(test));
+
+    proc mergesort(m);
+        if #m <= 1 then
+            return m;
+        end if;
+
+        middle := #m div 2;
+        left := mergesort(m(..middle));
+        right := mergesort(m(middle+1..));
+        if left(#left) <= right(1) then
+            return left + right;
+        end if;
+        return merge(left, right);
+    end proc;
+
+    proc merge(left, right);
+        result := [];
+        loop while left /= [] and right /= [] do
+            if left(1) <= right(1) then
+                item fromb left;
+            else
+                item fromb right;
+            end if;
+            result with:= item;
+        end loop;
+        return result + left + right;
+    end proc;
+end program;