Merge pull request neetcode-gh#2373 from Vishalkulkarni45/main

Update 0021-merge-two-sorted-lists.rs

Author: tahsintunan

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

@@ -0,0 +1,26 @@
+impl Solution {
+    pub fn remove_nth_from_end(head: Option<Box<ListNode>>, n: i32)-> Option<Box<ListNode>>  {
+     let mut list_len=0;
+     let mut cur=&head;
+     while let Some(node)=cur{
+         list_len+=1;
+         cur=&node.next;
+     }
+     let mut ans=Some(Box::new(ListNode{
+         val:1,
+         next:head
+     }));
+     let mut list=&mut ans;
+     let mut pos=0;
+     while let Some(node)=list{
+         if pos==list_len-n{
+             node.next=node.next.clone().unwrap().next.take();
+             break;
+         }
+         pos+=1;
+         list=&mut node.next;
+     }
+     ans.unwrap().next.take()
+    }
+}
+

rust/0021-merge-two-sorted-lists.rs

@@ -14,3 +14,31 @@ impl Solution {
         }
     }
 }
+//without recursion
+impl Solution {
+    pub fn merge_two_lists(mut list1: Option<Box<ListNode>>,mut list2: Option<Box<ListNode>>)->Option<Box<ListNode>>{
+        let mut ans=ListNode::new(1);
+        let mut cur=&mut ans;
+   
+   while let (Some(node1),Some(node2))=(list1.as_mut(),list2.as_mut()){
+   
+   if node1.val<node2.val{
+       cur.next=list1.take();
+       list1=cur.next.as_mut().unwrap().next.take();
+   }
+   else{
+       cur.next=list2.take();
+       list2=cur.next.as_mut().unwrap().next.take();
+   }
+   cur=cur.next.as_mut().unwrap();
+   }
+   cur.next=if list1.is_some(){
+       list1
+   }
+   else {
+       list2
+   };
+   ans.next
+}
+}
+