Add less verbose solution

Add another solution with hashmap instead of arrays for storing the count

Author: tayyabferozi

javascript/0424-longest-repeating-character-replacement.js

@@ -1,3 +1,30 @@
+/**
+ * https://leetcode.com/problems/longest-repeating-character-replacement/
+ * Time O(((N + 26) * N) * (M - N)) | Space O(1)
+ * @param {string} s
+ * @param {number} k
+ * @return {number}
+ */
+var characterReplacement = function(s, k) {
+    let res = 0;
+    let count = new Map();
+    let l = 0;
+
+    for (let r = 0; r < s.length; r++) {
+        let len  = r - l + 1
+        count.set(s[r], 1 + (count.get(s[r]) || 0))
+
+        if ((len - Math.max(...count.values())) > k) {
+            count.set(s[l], count.get(s[l]) - 1)
+            l++;
+        }
+        len = r - l + 1;
+        res = Math.max(res, len)
+    }
+
+    return res;
+};
+
 /**
  * https://leetcode.com/problems/longest-repeating-character-replacement/
  * Time O(((N + 26) * N) * (M - N)) | Space O(1)