Merge pull request #2625 from rmrt1n/019

Create 0019-remove-nth-node-from-end-of-list.rs

Author: tahsintunan

rust/0019-remove-nth-node-from-end-of-list.rs

@@ -0,0 +1,21 @@
+impl Solution {
+    pub fn remove_nth_from_end(head: Option<Box<ListNode>>, n: i32) -> Option<Box<ListNode>> {
+        let mut dummy = Box::new(ListNode { val: 0, next: head.clone() });
+        let (mut left, mut right) = (dummy.as_mut(), head);
+    
+        let mut n = n;
+        while n > 0 && right.is_some() {
+            right = right.unwrap().next;
+            n -= 1;
+        }
+    
+        while let Some(r) = right {
+            left = left.next.as_mut().unwrap();
+            right = r.next;
+        }
+    
+        left.next = left.next.take().unwrap().next.take();
+    
+        dummy.next
+    }
+}