Refactor code of the array shift to avoid the mods of the step variable

Author: Geektimus

src/main/java/com/codingmaniacs/codility/CollectionChallenges.java

@@ -61,16 +61,17 @@ public static boolean isOrderedBySingleSwap(int data[]) {
      * @return number array shifted to the right step times.
      */
     public static int[] arrayShiftRight(int[] ns, int step) {
+        int s = step;
         int nsLength = ns.length;
-        if (nsLength == 0 || nsLength == 1 || step == nsLength)
+        if (nsLength == 0 || nsLength == 1 || s == nsLength)
             return ns;
 
         int[] res = new int[nsLength];
 
-        step = (step % nsLength);
+        s %= nsLength;
 
-        int[] l = Arrays.copyOfRange(ns, 0, nsLength - step);
-        int[] r = Arrays.copyOfRange(ns, nsLength - step, nsLength);
+        int[] l = Arrays.copyOfRange(ns, 0, nsLength - s);
+        int[] r = Arrays.copyOfRange(ns, nsLength - s, nsLength);
 
         System.arraycopy(r, 0, res, 0, r.length);
         System.arraycopy(l, 0, res, r.length, l.length);