Add solution #904

Author: JoshCrozier

Diff for: README.md

@@ -714,6 +714,7 @@
 901|[Online Stock Span](./0901-online-stock-span.js)|Medium|
 902|[Numbers At Most N Given Digit Set](./0902-numbers-at-most-n-given-digit-set.js)|Hard|
 903|[Valid Permutations for DI Sequence](./0903-valid-permutations-for-di-sequence.js)|Hard|
+904|[Fruit Into Baskets](./0904-fruit-into-baskets.js)|Medium|
 905|[Sort Array By Parity](./0905-sort-array-by-parity.js)|Easy|
 909|[Snakes and Ladders](./0909-snakes-and-ladders.js)|Medium|
 912|[Sort an Array](./0912-sort-an-array.js)|Medium|

Diff for: solutions/0904-fruit-into-baskets.js

@@ -0,0 +1,46 @@
+/**
+ * 904. Fruit Into Baskets
+ * https://leetcode.com/problems/fruit-into-baskets/
+ * Difficulty: Medium
+ *
+ * You are visiting a farm that has a single row of fruit trees arranged from left to right.
+ * The trees are represented by an integer array fruits where fruits[i] is the type of fruit
+ * the ith tree produces.
+ *
+ * You want to collect as much fruit as possible. However, the owner has some strict rules
+ * that you must follow:
+ * - You only have two baskets, and each basket can only hold a single type of fruit. There
+ *   is no limit on the amount of fruit each basket can hold.
+ * - Starting from any tree of your choice, you must pick exactly one fruit from every tree
+ *   (including the start tree) while moving to the right. The picked fruits must fit in one
+ *   of your baskets.
+ * - Once you reach a tree with fruit that cannot fit in your baskets, you must stop.
+ *
+ * Given the integer array fruits, return the maximum number of fruits you can pick.
+ */
+
+/**
+ * @param {number[]} fruits
+ * @return {number}
+ */
+var totalFruit = function(fruits) {
+  const map = new Map();
+  let result = 0;
+  let start = 0;
+
+  for (let end = 0; end < fruits.length; end++) {
+    map.set(fruits[end], (map.get(fruits[end]) || 0) + 1);
+
+    while (map.size > 2) {
+      map.set(fruits[start], map.get(fruits[start]) - 1);
+      if (map.get(fruits[start]) === 0) {
+        map.delete(fruits[start]);
+      }
+      start++;
+    }
+
+    result = Math.max(result, end - start + 1);
+  }
+
+  return result;
+};