Add solution #383

Author: JoshCrozier

README.md

@@ -52,6 +52,7 @@
 347|[Top K Frequent Elements](./0347-top-k-frequent-elements.js)|Medium|
 349|[Intersection of Two Arrays](./0349-intersection-of-two-arrays.js)|Easy|
 350|[Intersection of Two Arrays II](./0350-intersection-of-two-arrays-ii.js)|Easy|
+383|[Ransom Note](./0383-ransom-note.js)|Easy|
 387|[First Unique Character in a String](./0387-first-unique-character-in-a-string.js)|Easy|
 448|[Find All Numbers Disappeared in an Array](./0448-find-all-numbers-disappeared-in-an-array.js)|Easy|
 451|[Sort Characters By Frequency](./0451-sort-characters-by-frequency.js)|Medium|

solutions/0383-ransom-note.js

@@ -0,0 +1,32 @@
+/**
+ * 383. Ransom Note
+ * https://leetcode.com/problems/ransom-note/
+ * Difficulty: Easy
+ *
+ * Given two stings ransomNote and magazine, return true if ransomNote
+ * can be constructed from magazine and false otherwise.
+ *
+ * Each letter in magazine can only be used once in ransomNote.
+ */
+
+/**
+ * @param {string} ransomNote
+ * @param {string} magazine
+ * @return {boolean}
+ */
+var canConstruct = function(ransomNote, magazine) {
+  const map = new Map();
+
+  for (let i = magazine.length - 1; i > -1; i--) {
+    map.set(magazine[i], (map.get(magazine[i]) || 0) + 1);
+  }
+
+  for (let i = ransomNote.length - 1; i > -1; i--) {
+    if ((map.get(ransomNote[i]) || 0) < 1) {
+      return false;
+    }
+    map.set(ransomNote[i], map.get(ransomNote[i]) - 1);
+  }
+
+  return true;
+};