import java.util.List;
import java.util.Random;

/** HW10, problem #3.
 *  @author
 */
public class Shuffle {
    /** Returns the result of non-destructively riffle-shuffling the
     *  two lists of T L1 and L2 together, using the
     *  Gilbert-Shannon-Reeds model, with R supplying pseudo-random
     *  numbers (so that shuffling the same lists twice with a
     *  generator starting in the same state both times results in the
     *  same list).
     */
    static <T> List<T> riffle(List<T> L1, List<T> L2, Random R) {
        // REPLACE WITH ANSWER
        return null;
    }
}