Add solution #1297

Author: JoshCrozier

solutions/1297-maximum-number-of-occurrences-of-a-substring.js

@@ -0,0 +1,32 @@
+/**
+ * 1297. Maximum Number of Occurrences of a Substring
+ * https://leetcode.com/problems/maximum-number-of-occurrences-of-a-substring/
+ * Difficulty: Medium
+ *
+ * Given a string s, return the maximum number of ocurrences of
+ * any substring under the following rules:
+ *
+ * - The number of unique characters in the substring must be less
+ *   than or equal to maxLetters.
+ * - The substring size must be between minSize and maxSize inclusive.
+ */
+
+/**
+ * @param {string} s
+ * @param {number} maxLetters
+ * @param {number} minSize
+ * @param {number} maxSize
+ * @return {number}
+ */
+var maxFreq = function(s, maxLetters, minSize, maxSize) {
+  const occurrences = new Map();
+
+  for (let i = 0; i <= s.length - minSize; i++) {
+    const string = s.substr(i, minSize);
+    if (new Set(string.split('')).size <= maxLetters) {
+      occurrences.set(string, occurrences.has(string) ? occurrences.get(string) + 1 : 1);
+    }
+  }
+
+  return (Array.from(occurrences).sort((a, b) => b[1] - a[1])[0] || [])[1] || 0;
+};