kt: add «2033. Minimum Operations to Make a Uni-Value Grid»

URL:	https://leetcode.com/problems/minimum-operations-to-make-a-uni-value-grid/
Signed-off-by: Matej Focko <me@mfocko.xyz>

kt/minimum-operations-to-make-a-uni-value-grid.kt

@@ -0,0 +1,31 @@
+class Solution {
+    fun minOperations(
+        grid: Array<IntArray>,
+        x: Int,
+    ): Int {
+        if (grid.any { row -> row.any { it -> it % x != grid[0][0] % x } }) {
+            // can't make them equal by a multiple of ‹x›
+            return -1
+        }
+
+        val nums = grid.flatMap { it.asIterable() }.sorted()
+
+        var ops = 0
+
+        var (l, r) = 0 to nums.size - 1
+        while (l < r) {
+            when {
+                l < nums.size - r - 1 -> {
+                    ops += (l + 1) * (nums[l + 1] - nums[l]) / x
+                    l++
+                }
+                else -> {
+                    ops += (nums.size - r) * (nums[r] - nums[r - 1]) / x
+                    r--
+                }
+            }
+        }
+
+        return ops
+    }
+}