rs: add «2966. Divide Array Into Arrays With Max Difference»

Signed-off-by: Matej Focko <me@mfocko.xyz>

rs/divide-array-into-arrays-with-max-difference.rs

@@ -0,0 +1,18 @@
+impl Solution {
+    pub fn divide_array(mut nums: Vec<i32>, k: i32) -> Vec<Vec<i32>> {
+        nums.sort();
+
+        let divisions: Vec<Vec<i32>> = nums.as_slice().chunks_exact(3).map(Vec::from).collect();
+
+        for d in &divisions {
+            let first = d.first().expect("must have first element");
+            let last = d.last().expect("we are guaranteed triples");
+
+            if last - first > k {
+                return vec![];
+            }
+        }
+
+        divisions
+    }
+}