Saurav and Dravid play the following game on the board which is a rectangle 1 × 10 divided into 10 consecutive squares. There is a coin on the ﬁrst square. Each player in his turn can move it forward by one,two or three squares. The winner is the one who ﬁnishes ﬁrst by placing the coin on the last (tenth) square. Saurav starts ﬁrst. How he should play in order to win regardless of the moves of his opponent?