<p>A cinema has <code>n</code> rows of seats, numbered from 1 to <code>n</code> and there are ten seats in each row, labelled from 1 to 10 as shown in the figure above.</p>
<p>Given the array <code>reservedSeats</code> containing the numbers of seats already reserved, for example, <code>reservedSeats[i] = [3,8]</code> means the seat located in row <strong>3</strong> and labelled with <b>8</b> is already reserved.</p>
<p><em>Return the maximum number of four-person groups you can assign on the cinema seats.</em> A four-person group occupies four adjacent seats <strong>in one single row</strong>. Seats across an aisle (such as [3,3] and [3,4]) are not considered to be adjacent, but there is an exceptional case on which an aisle split a four-person group, in that case, the aisle split a four-person group in the middle, which means to have two people on each side.</p>
<strong>Input:</strong> n = 3, reservedSeats = [[1,2],[1,3],[1,8],[2,6],[3,1],[3,10]]
<strong>Output:</strong> 4
<strong>Explanation:</strong> The figure above shows the optimal allocation for four groups, where seats mark with blue are already reserved and contiguous seats mark with orange are for one group.
