Merge pull request #2297 from yaxarat/kotlin

Match Kotlin solution for 973 to the video solution

Author: a93a

kotlin/0973-k-closest-points-to-origin.kt

@@ -1,12 +1,43 @@
+/**
+Solution using min heap
+ */
+class Solution {
+    fun kClosest(points: Array<IntArray>, k: Int): Array<IntArray> {
+        val minHeap = PriorityQueue<IntArray> { a, b -> a[0] - b[0] }
+        val result = Array<IntArray>(k) { IntArray(2) { 0 } }
+        
+        for (point in points) {
+            minHeap.add(
+                intArrayOf(
+                    /* distance from (0,0) */ point[0].squared() + point[1].squared(),
+                    /* x coordinate */ point[0],
+                    /* y coordinate */ point[1]
+                )
+            )
+        }
+
+        for (i in 0 until k) {
+            val pointWithDistance = minHeap.poll()
+            result[i][0] = pointWithDistance[1]
+            result[i][1] = pointWithDistance[2]
+        }
+
+        return result
+    }
+
+    private fun Int.squared() = this * this
+}
+
+/**
+Solution using built in sort function
+ */
 class Solution {
     fun kClosest(points: Array<IntArray>, k: Int): Array<IntArray> {
         val sorted = points.sortedBy{ it[0]*it[0] + it[1]*it[1]}
         val list = arrayListOf<IntArray>()
-
         for (i in 0..k-1) {
             list.add(sorted[i])
         }
-
         return list.toTypedArray()
     }
 }