Add solution #1386

Author: JoshCrozier

README.md

@@ -1,4 +1,4 @@
-# 1,269 LeetCode solutions in JavaScript
+# 1,270 LeetCode solutions in JavaScript
 
 [https://leetcodejavascript.com](https://leetcodejavascript.com)
 
@@ -1056,6 +1056,7 @@
 1382|[Balance a Binary Search Tree](./solutions/1382-balance-a-binary-search-tree.js)|Medium|
 1383|[Maximum Performance of a Team](./solutions/1383-maximum-performance-of-a-team.js)|Hard|
 1385|[Find the Distance Value Between Two Arrays](./solutions/1385-find-the-distance-value-between-two-arrays.js)|Easy|
+1386|[Cinema Seat Allocation](./solutions/1386-cinema-seat-allocation.js)|Medium|
 1389|[Create Target Array in the Given Order](./solutions/1389-create-target-array-in-the-given-order.js)|Easy|
 1400|[Construct K Palindrome Strings](./solutions/1400-construct-k-palindrome-strings.js)|Medium|
 1402|[Reducing Dishes](./solutions/1402-reducing-dishes.js)|Hard|

solutions/1386-cinema-seat-allocation.js

@@ -0,0 +1,53 @@
+/**
+ * 1386. Cinema Seat Allocation
+ * https://leetcode.com/problems/cinema-seat-allocation/
+ * Difficulty: Medium
+ *
+ * A cinema has n rows of seats, numbered from 1 to n and there are ten seats in each row, labelled
+ * from 1 to 10 as shown in the figure above.
+ *
+ * Given the array reservedSeats containing the numbers of seats already reserved, for example,
+ * reservedSeats[i] = [3,8] means the seat located in row 3 and labelled with 8 is already reserved.
+ *
+ * Return the maximum number of four-person groups you can assign on the cinema seats. A four-person
+ * group occupies four adjacent seats in one single row. 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.
+ */
+
+/**
+ * @param {number} n
+ * @param {number[][]} reservedSeats
+ * @return {number}
+ */
+var maxNumberOfFamilies = function(n, reservedSeats) {
+  const rowReservations = new Map();
+
+  for (const [row, seat] of reservedSeats) {
+    if (!rowReservations.has(row)) {
+      rowReservations.set(row, new Set());
+    }
+    rowReservations.get(row).add(seat);
+  }
+
+  let result = 2 * (n - rowReservations.size);
+
+  for (const seats of rowReservations.values()) {
+    let canPlaceGroup = false;
+
+    if (!seats.has(2) && !seats.has(3) && !seats.has(4) && !seats.has(5)) {
+      result++;
+      canPlaceGroup = true;
+    }
+    if (!seats.has(6) && !seats.has(7) && !seats.has(8) && !seats.has(9)) {
+      result++;
+      canPlaceGroup = true;
+    }
+    if (!canPlaceGroup && !seats.has(4) && !seats.has(5) && !seats.has(6) && !seats.has(7)) {
+      result++;
+    }
+  }
+
+  return result;
+};