Add solution #846

Author: JoshCrozier

README.md

@@ -89,6 +89,7 @@
 824|[Goat Latin](./0824-goat-latin.js)|Easy|
 831|[Masking Personal Information](./0831-masking-personal-information.js)|Medium|
 844|[Backspace String Compare](./0844-backspace-string-compare.js)|Easy|
+846|[Hand of Straights](./0846-hand-of-straights.js)|Medium|
 867|[Transpose Matrix](./0867-transpose-matrix.js)|Easy|
 884|[Uncommon Words from Two Sentences](./0884-uncommon-words-from-two-sentences.js)|Easy|
 890|[Find and Replace Pattern](./0890-find-and-replace-pattern.js)|Medium|

solutions/0846-hand-of-straights.js

@@ -0,0 +1,43 @@
+/**
+ * 846. Hand of Straights
+ * https://leetcode.com/problems/hand-of-straights/
+ * Difficulty: Medium
+ *
+ * Alice has some number of cards and she wants to rearrange
+ * the cards into groups so that each group is of size groupSize,
+ * and consists of groupSize consecutive cards.
+ *
+ * Given an integer array hand where hand[i] is the value written
+ * on the ith card and an integer groupSize, return true if she
+ * can rearrange the cards, or false otherwise.
+ */
+
+/**
+ * @param {number[]} hand
+ * @param {number} groupSize
+ * @return {boolean}
+ */
+var isNStraightHand = function(hand, groupSize) {
+  if (hand.length % groupSize) {
+    return false;
+  }
+
+  const map = {};
+  const set = new Set(hand);
+  hand.forEach(x => map[x] ? map[x]++ : map[x] = 1);
+
+  let count = hand.length / groupSize;
+  while (count--) {
+    let min = Math.min(...set);
+    for (let i = min; i < min + groupSize; i++) {
+      if (!map[i]) {
+        return false;
+      }
+      if (!--map[i]) {
+        set.delete(i);
+      }
+    }
+  }
+
+  return true;
+};