Add solution #2559

Author: JoshCrozier

README.md

@@ -768,6 +768,7 @@
 2529|[Maximum Count of Positive Integer and Negative Integer](./2529-maximum-count-of-positive-integer-and-negative-integer.js)|Easy|
 2535|[Difference Between Element Sum and Digit Sum of an Array](./2535-difference-between-element-sum-and-digit-sum-of-an-array.js)|Easy|
 2542|[Maximum Subsequence Score](./2542-maximum-subsequence-score.js)|Medium|
+2559|[Count Vowel Strings in Ranges](./2559-count-vowel-strings-in-ranges.js)|Medium|
 2570|[Merge Two 2D Arrays by Summing Values](./2570-merge-two-2d-arrays-by-summing-values.js)|Easy|
 2579|[Count Total Number of Colored Cells](./2579-count-total-number-of-colored-cells.js)|Medium|
 2618|[Check if Object Instance of Class](./2618-check-if-object-instance-of-class.js)|Medium|

solutions/2559-count-vowel-strings-in-ranges.js

@@ -0,0 +1,28 @@
+/**
+ * 2559. Count Vowel Strings in Ranges
+ * https://leetcode.com/problems/count-vowel-strings-in-ranges/
+ * Difficulty: Medium
+ *
+ * You are given a 0-indexed array of strings words and a 2D array of integers queries.
+ *
+ * Each query queries[i] = [li, ri] asks us to find the number of strings present at the
+ * indices ranging from li to ri (both inclusive) of words that start and end with a vowel.
+ *
+ * Return an array ans of size queries.length, where ans[i] is the answer to the ith query.
+ *
+ * Note that the vowel letters are 'a', 'e', 'i', 'o', and 'u'.
+ */
+
+/**
+ * @param {string[]} words
+ * @param {number[][]} queries
+ * @return {number[]}
+ */
+var vowelStrings = function(words, queries) {
+  const vowels = new Set(['a', 'e', 'i', 'o', 'u']);
+  const prefix = [0];
+  for (let i = 0; i < words.length; i++) {
+    prefix[i + 1] = prefix[i] + (vowels.has(words[i][0]) && vowels.has(words[i].at(-1)));
+  }
+  return queries.map(([l, r]) => prefix[r + 1] - prefix[l]);
+};