problems: add maximum numbers of coins you can get

problems/maximum-number-of-coins-you-can-get.rs

@@ -0,0 +1,14 @@
+impl Solution {
+    pub fn max_coins(piles: Vec<i32>) -> i32 {
+        let mut sorted_piles = piles.clone();
+        sorted_piles.sort();
+        
+        sorted_piles
+            .iter()
+            .rev()
+            .skip(1)
+            .step_by(2)
+            .take(piles.len() / 3)
+            .sum()
+    }
+}