@@ -24,6 +24,7 @@ My solutions to LeetCode problems in Kotlin.
 | [796](https://leetcode.com/problems/rotate-string/) | [Rotate String](src/main/kotlin/com/schmoczer/leetcode/_0796/RotateString.kt) | Easy |
 | [1574](https://leetcode.com/problems/shortest-subarray-to-be-removed-to-make-array-sorted/) | [Shortest Subarray to be Removed to Make Array Sorted](src/main/kotlin/com/schmoczer/leetcode/_1574/ShortestSubarray.kt) | Medium |
 | [1829](https://leetcode.com/problems/maximum-xor-for-each-query/) | [Maximum XOR for Each Query](src/main/kotlin/com/schmoczer/leetcode/_1829/MaximumXorForEachQuery.kt) | Medium |
+| [1861](https://leetcode.com/problems/rotating-the-box/) | [Rotating the Box](src/main/kotlin/com/schmoczer/leetcode/_1861/RotatingTheBox.kt) | Medium |
 | [1957](https://leetcode.com/problems/delete-characters-to-make-fancy-string/) | [Delete Characters to Make Fancy String](src/main/kotlin/com/schmoczer/leetcode/_1957/DeleteCharactersToMakeFancyString.kt) | Easy |
 | [2064](https://leetcode.com/problems/minimized-maximum-of-products-distributed-to-any-store/) | [Minimized Maximum of Products Distributed to Any Store](src/main/kotlin/com/schmoczer/leetcode/_2064/MinimizedMaximum.kt) | Medium |
 | [2070](https://leetcode.com/problems/most-beautiful-item-for-each-query/) | [Most Beautiful Item for Each Query](src/main/kotlin/com/schmoczer/leetcode/_2070/MostBeautifulItemForEachQuery.kt) | Medium |

@@ -0,0 +1,55 @@
+# Rotating the Box
+
+You are given an `m x n` matrix of characters `box` representing a side-view of a box. Each cell of the box is one of
+the following:
+
+- A stone `'#'`
+- A stationary obstacle `'*'`
+- Empty `'.'`
+
+The box is rotated 90 degrees clockwise, causing some of the stones to fall due to gravity. Each stone falls down until
+it lands on an obstacle, another stone, or the bottom of the box. Gravity does not affect the obstacles' positions, and
+the inertia from the box's rotation does not affect the stones' horizontal positions.
+
+It is guaranteed that each stone in `box` rests on an obstacle, another stone, or the bottom of the box.
+
+Return an `n x m` matrix representing the box after the rotation described above.
+
+Example 1:
+
+> Input: box = [["#",".","#"]]
+>
+> Output: [["."],
+["#"],
+["#"]]
+
+Example 2:
+
+> Input: box = [["#",".","*","."],
+["#","#","*","."]]
+>
+> Output: [["#","."],
+["#","#"],
+["*","*"],
+[".","."]]
+
+Example 3:
+
+> Input: box = [["#","#","*",".","*","."],
+["#","#","#","*",".","."],
+["#","#","#",".","#","."]]
+>
+> Output: [[".","#","#"],
+[".","#","#"],
+["#","#","*"],
+["#","*","."],
+["#",".","*"],
+["#",".","."]]
+
+
+Constraints:
+
+- `m == box.length`
+- `n == box[i].length`
+- `1 <= m, n <= 500`
+- `box[i][j]` is either `'#'`, `'*'`, or `'.'.`

@@ -0,0 +1,41 @@
+package com.schmoczer.leetcode._1861
+
+class RotatingTheBox {
+fun rotateTheBox(box: Array<CharArray>): Array<CharArray> {
+if (box.isEmpty()) {
+return emptyArray()
+}
+for (row in box) {
+var lastStarFound: Int? = null
+var lastDotFound: Int? = null
+for (i in row.size - 1 downTo 0) {
+when (row[i]) {
+'.' -> {
+if (lastDotFound == null) {
+lastDotFound = i
+}
+}
+
+'*' -> {
+lastStarFound = i
+lastDotFound = null
+}
+
+'#' -> {
+if (lastDotFound != null) {
+row[lastDotFound] = '#'
+row[i] = '.'
+lastDotFound--
+}
+}
+}
+}
+}
+
+return Array(box[0].size) { x ->
+CharArray(box.size) { y ->
+box[box.size - y - 1][x]
+}
+}
+}
+}

@@ -0,0 +1,73 @@
+package com.schmoczer.leetcode._1861
+
+import org.junit.jupiter.api.BeforeEach
+import kotlin.test.Test
+import kotlin.test.assertContentEquals
+
+class RotatingTheBoxTest {
+private lateinit var sut: RotatingTheBox
+
+@BeforeEach
+fun setUp() {
+sut = RotatingTheBox()
+}
+
+@Test
+fun `matrix with 1 row rotated`() {
+val input = arrayOf(charArrayOf('#', '.', '#'))
+val expected = arrayOf(
+charArrayOf('.'),
+charArrayOf('#'),
+charArrayOf('#'),
+)
+
+val result = sut.rotateTheBox(input)
+
+for (i in 0 until expected.size) {
+assertContentEquals(expected[i], result[i])
+}
+}
+
+@Test
+fun `matrix with 2 rows rotated`() {
+val input = arrayOf(
+charArrayOf('#', '.', '*', '.'),
+charArrayOf('#', '#', '*', '.'),
+)
+val expected = arrayOf(
+charArrayOf('#', '.'),
+charArrayOf('#', '#'),
+charArrayOf('*', '*'),
+charArrayOf('.', '.'),
+)
+
+val result = sut.rotateTheBox(input)
+
+for (i in 0 until expected.size) {
+assertContentEquals(expected[i], result[i])
+}
+}
+
+@Test
+fun `matrix with 3 rows rotated`() {
+val input = arrayOf(
+charArrayOf('#', '#', '*', '.', '*', '.'),
+charArrayOf('#', '#', '#', '*', '.', '.'),
+charArrayOf('#', '#', '#', '.', '#', '.'),
+)
+val expected = arrayOf(
+charArrayOf('.', '#', '#'),
+charArrayOf('.', '#', '#'),
+charArrayOf('#', '#', '*'),
+charArrayOf('#', '*', '.'),
+charArrayOf('#', '.', '*'),
+charArrayOf('#', '.', '.'),
+)
+
+val result = sut.rotateTheBox(input)
+
+for (i in 0 until expected.size) {
+assertContentEquals(expected[i], result[i])
+}
+}
+}