add Kotlin solution for 846. Hand of Straights

Author: technophilist

kotlin/0846-hand-of-straights.kt

@@ -0,0 +1,28 @@
+class Solution {
+    fun isNStraightHand(hand: IntArray, groupSize: Int): Boolean {
+        if (hand.size % groupSize != 0) return false
+        val countMap = mutableMapOf<Int, Int>()
+        hand.forEach { countMap[it] = countMap.getOrDefault(it, 0) + 1 }
+        val minHeap = PriorityQueue(countMap.keys)
+
+        while (minHeap.isNotEmpty()) {
+            val minValue = minHeap.peek()
+            if (countMap.getValue(minValue) == 0) {
+                minHeap.remove()
+                continue
+            }
+            // loop through consecutive numbers starting from the "minValue" number
+            for (consecutiveNumber in minValue until (minValue + groupSize)) {
+                if (
+                    consecutiveNumber !in countMap.keys ||
+                    countMap.getValue(consecutiveNumber) == 0
+                ) return false
+                countMap[consecutiveNumber] = countMap.getValue(consecutiveNumber) - 1
+            }
+            // if the loop successfully executes without returning, it indicates that
+            // it was possible to create a group of size [groupSize] with minValue
+            // as the first element in the group.
+        }
+        return true
+    }
+}