Initial data commit

Task/Sorting-algorithms-Radix-sort/Nim/sorting-algorithms-radix-sort.nim

@@ -0,0 +1,33 @@
+func radixSort[T](a: openArray[T]): seq[T] =
+
+  result = @a
+
+  ## Loop for every bit in the integers.
+  for shift in countdown(63, 0):
+    var tmp = newSeq[T](result.len)   # The array to put the partially sorted array into.
+    var j = 0                         # The number of 0s.
+    for i in 0..result.high:
+      # If there is a 1 in the bit we are testing, the number will be negative.
+      let move = result[i] shl shift >= 0
+      # If this is the last bit, negative numbers are actually lower.
+      let toBeMoved = if shift == 0: not move else: move
+      if toBeMoved:
+        tmp[j] = result[i]
+        inc j
+      else:
+        # It's a 1, so stick it in the result array for now.
+        result[i - j] = result[i]
+    # Copy over the 1s from the old array.
+    for i in j..tmp.high:
+      tmp[i] = result[i - j]
+    # And now the tmp array gets switched for another round of sorting.
+    result =move(tmp)
+
+
+when isMainModule:
+
+  const arrays = [@[170, 45, 75, -90, -802, 24, 2, 66],
+                  @[-4, 5, -26, 58, -990, 331, 331, 990, -1837, 2028]]
+
+  for a in arrays:
+    echo radixSort(a)