Add solution #697

Author: JoshCrozier

README.md

@@ -257,6 +257,7 @@
 680|[Valid Palindrome II](./0680-valid-palindrome-ii.js)|Easy|
 686|[Repeated String Match](./0686-repeated-string-match.js)|Easy|
 695|[Max Area of Island](./0695-max-area-of-island.js)|Medium|
+697|[Degree of an Array](./0697-degree-of-an-array.js)|Easy|
 700|[Search in a Binary Search Tree](./0700-search-in-a-binary-search-tree.js)|Easy|
 701|[Insert into a Binary Search Tree](./0701-insert-into-a-binary-search-tree.js)|Medium|
 704|[Binary Search](./0704-binary-search.js)|Easy|

solutions/0697-degree-of-an-array.js

@@ -0,0 +1,39 @@
+/**
+ * 697. Degree of an Array
+ * https://leetcode.com/problems/degree-of-an-array/
+ * Difficulty: Easy
+ *
+ * Given a non-empty array of non-negative integers nums, the degree of this array is
+ * defined as the maximum frequency of any one of its elements.
+ *
+ * Your task is to find the smallest possible length of a (contiguous) subarray of
+ * nums, that has the same degree as nums.
+ */
+
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var findShortestSubArray = function(nums) {
+  const map = new Map();
+
+  nums.forEach((key, index) => {
+    if (!map.has(key)) {
+      map.set(key, { start: index, end: index, count: 1 });
+    }
+    const { start, end, count } = map.get(key);
+    map.set(key, { start, end: index, count: count + 1 });
+  });
+
+  let max = 0;
+  let result = Infinity;
+  Array.from(map).forEach(([_, { start, end, count }]) => {
+    const min = (end - start) + 1;
+    if (count > max || (min < result && count === max)) {
+      result = min;
+      max = count;
+    }
+  });
+
+  return result;
+};