Add solution #299

Author: JoshCrozier

README.md

@@ -244,6 +244,7 @@
 292|[Nim Game](./0292-nim-game.js)|Easy|
 295|[Find Median from Data Stream](./0295-find-median-from-data-stream.js)|Hard|
 297|[Serialize and Deserialize Binary Tree](./0297-serialize-and-deserialize-binary-tree.js)|Hard|
+299|[Bulls and Cows](./0299-bulls-and-cows.js)|Medium|
 300|[Longest Increasing Subsequence](./0300-longest-increasing-subsequence.js)|Medium|
 303|[Range Sum Query - Immutable](./0303-range-sum-query-immutable.js)|Easy|
 306|[Additive Number](./0306-additive-number.js)|Medium|

solutions/0299-bulls-and-cows.js

@@ -0,0 +1,44 @@
+/**
+ * 299. Bulls and Cows
+ * https://leetcode.com/problems/bulls-and-cows/
+ * Difficulty: Medium
+ *
+ * You are playing the Bulls and Cows game with your friend.
+ *
+ * You write down a secret number and ask your friend to guess what the number is.
+ * When your friend makes a guess, you provide a hint with the following info:
+ * - The number of "bulls", which are digits in the guess that are in the correct position.
+ * - The number of "cows", which are digits in the guess that are in your secret number but
+ *   are located in the wrong position. Specifically, the non-bull digits in the guess that
+ *   could be rearranged such that they become bulls.
+ *
+ * Given the secret number secret and your friend's guess guess, return the hint for your
+ * friend's guess.
+ *
+ * The hint should be formatted as "xAyB", where x is the number of bulls and y is the number
+ * of cows. Note that both secret and guess may contain duplicate digits.
+ */
+
+/**
+ * @param {string} secret
+ * @param {string} guess
+ * @return {string}
+ */
+var getHint = function(secret, guess) {
+  const map = Array(10).fill(0);
+  let a = 0;
+  let b = 0;
+
+  for (const i in secret) {
+    if (secret[i] === guess[i]) {
+      a++;
+    } else {
+      map[secret[i]]++;
+      map[guess[i]]--;
+      b += map[secret[i]] <= 0;
+      b += map[guess[i]] >= 0;
+    }
+  }
+
+  return `${a}A${b}B`;
+};