Add solution #1625

Author: JoshCrozier

README.md

@@ -1,4 +1,4 @@
-# 1,429 LeetCode solutions in JavaScript
+# 1,430 LeetCode solutions in JavaScript
 
 [https://leetcodejavascript.com](https://leetcodejavascript.com)
 
@@ -1253,6 +1253,7 @@
 1621|[Number of Sets of K Non-Overlapping Line Segments](./solutions/1621-number-of-sets-of-k-non-overlapping-line-segments.js)|Medium|
 1622|[Fancy Sequence](./solutions/1622-fancy-sequence.js)|Hard|
 1624|[Largest Substring Between Two Equal Characters](./solutions/1624-largest-substring-between-two-equal-characters.js)|Easy|
+1625|[Lexicographically Smallest String After Applying Operations](./solutions/1625-lexicographically-smallest-string-after-applying-operations.js)|Medium|
 1657|[Determine if Two Strings Are Close](./solutions/1657-determine-if-two-strings-are-close.js)|Medium|
 1668|[Maximum Repeating Substring](./solutions/1668-maximum-repeating-substring.js)|Easy|
 1669|[Merge In Between Linked Lists](./solutions/1669-merge-in-between-linked-lists.js)|Medium|

solutions/1625-lexicographically-smallest-string-after-applying-operations.js

@@ -0,0 +1,60 @@
+/**
+ * 1625. Lexicographically Smallest String After Applying Operations
+ * https://leetcode.com/problems/lexicographically-smallest-string-after-applying-operations/
+ * Difficulty: Medium
+ *
+ * You are given a string s of even length consisting of digits from 0 to 9, and two integers a
+ * and b.
+ *
+ * You can apply either of the following two operations any number of times and in any order on s:
+ * - Add a to all odd indices of s (0-indexed). Digits post 9 are cycled back to 0. For example,
+ *   if s = "3456" and a = 5, s becomes "3951".
+ * - Rotate s to the right by b positions. For example, if s = "3456" and b = 1, s becomes "6345".
+ *
+ * Return the lexicographically smallest string you can obtain by applying the above operations any
+ * number of times on s.
+ *
+ * A string a is lexicographically smaller than a string b (of the same length) if in the first
+ * position where a and b differ, string a has a letter that appears earlier in the alphabet than
+ * the corresponding letter in b. For example, "0158" is lexicographically smaller than "0190"
+ * because the first position they differ is at the third letter, and '5' comes before '9'.
+ */
+
+/**
+ * @param {string} s
+ * @param {number} a
+ * @param {number} b
+ * @return {string}
+ */
+var findLexSmallestString = function(s, a, b) {
+  const visited = new Set();
+  let smallestString = s;
+  const queue = [s];
+
+  const addOperation = str => {
+    const chars = str.split('');
+    for (let i = 1; i < str.length; i += 2) {
+      chars[i] = String((parseInt(chars[i]) + a) % 10);
+    }
+    return chars.join('');
+  };
+
+  const rotateOperation = str => {
+    return str.slice(-b) + str.slice(0, -b);
+  };
+
+  while (queue.length) {
+    const current = queue.shift();
+    if (visited.has(current)) continue;
+    visited.add(current);
+    if (current < smallestString) smallestString = current;
+
+    const added = addOperation(current);
+    const rotated = rotateOperation(current);
+
+    queue.push(added);
+    queue.push(rotated);
+  }
+
+  return smallestString;
+};