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Task/Sorting-algorithms-Quicksort/Lua/sorting-algorithms-quicksort.lua

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+--in-place quicksort
+function quicksort(t, start, endi)
+  start, endi = start or 1, endi or #t
+  --partition w.r.t. first element
+  if(endi - start < 2) then return t end
+  local pivot = start
+  for i = start + 1, endi do
+    if t[i] <= t[pivot] then
+      local temp = t[pivot + 1]
+      t[pivot + 1] = t[pivot]
+      if(i == pivot + 1) then
+        t[pivot] = temp
+      else
+        t[pivot] = t[i]
+        t[i] = temp
+      end
+      pivot = pivot + 1
+    end
+  end
+  t = quicksort(t, start, pivot - 1)
+  return quicksort(t, pivot + 1, endi)
+end
+
+--example
+print(unpack(quicksort{5, 2, 7, 3, 4, 7, 1}))