ListNode struct is now in its own module linked_list, added list! macro for easier linked list creations, added tests for p2 and p19

src/lib.rs

@@ -1,3 +1,5 @@
+#[macro_use]
+pub mod linked_list;
 pub mod p1_two_sum;
 pub mod p2_add_two_numbers;
 pub mod p3_longest_substring_without_repeating_characters;
@@ -16,3 +18,4 @@ pub mod p15_3sum;
 pub mod p16_3sum_closest;
 pub mod p17_letter_combinations_of_a_phone_number;
 pub mod p18_4sum;
+pub mod p19_remove_nth_node_from_end_of_list;

src/linked_list.rs

@@ -0,0 +1,32 @@
+#[derive(PartialEq, Eq, Clone, Debug)]
+pub struct ListNode {
+    pub val: i32,
+    pub next: Option<Box<ListNode>>
+}
+
+impl ListNode {
+    #[inline]
+    pub fn new(val: i32) -> Self {
+        Self { next: None, val }
+    }
+}
+
+#[macro_export]
+macro_rules! list {
+    () => { None };
+    ( $first:expr ) => { Some(Box::new(ListNode::new($first))) };
+    ( $first:expr, $($x:expr),* ) => {
+        {
+            let mut head = Box::new(ListNode::new($first));
+            let mut tail = &mut head;
+            #[allow(unused_assignments)]
+            {
+                $(
+                    tail.next = Some(Box::new(ListNode::new($x)));
+                    tail = tail.next.as_mut().unwrap();
+                )*
+            }
+            Some(head)
+        }
+    };
+}

src/p19_remove_nth_node_from_end_of_list.rs

@@ -0,0 +1,23 @@
+use super::linked_list::ListNode;
+
+struct Solution;
+impl Solution {
+    pub fn remove_nth_from_end(head: Option<Box<ListNode>>, n: i32) -> Option<Box<ListNode>> {
+        return None;
+    }
+}
+
+#[test]
+fn test1() {
+    assert_eq!(Solution::remove_nth_from_end(list![1,2,3,4,5], 2), list![1,2,3,5]);
+}
+
+#[test]
+fn test2() {
+    assert_eq!(Solution::remove_nth_from_end(list![1], 1), list![]);
+}
+
+#[test]
+fn test3() {
+    assert_eq!(Solution::remove_nth_from_end(list![1,2], 1), list![1]);
+}

src/p2_add_two_numbers.rs

@@ -1,3 +1,5 @@
+use super::linked_list::ListNode;
+
 pub struct Solution;
 impl Solution {
     pub fn add_two_numbers(l1: Option<Box<ListNode>>, l2: Option<Box<ListNode>>) -> Option<Box<ListNode>> {
@@ -27,24 +29,17 @@ impl Solution {
     }    
 }
 
-// Definition for singly-linked list.
-#[derive(PartialEq, Eq, Clone, Debug)]
-pub struct ListNode {
-    pub val: i32,
-    pub next: Option<Box<ListNode>>
-}
-
-impl ListNode {
-    #[inline]
-    fn new(val: i32) -> Self {
-        ListNode {
-            next: None,
-            val
-        }
-    }
+#[test]
+fn test1() {
+    assert_eq!(Solution::add_two_numbers(list![2,4,3], list![5,6,4]), list![7,0,8]);
 }
 
 #[test]
-fn test() {
-    
+fn test2() {
+    assert_eq!(Solution::add_two_numbers(list![0], list![0]), list![0]);
+}
+
+#[test]
+fn test3() {
+    assert_eq!(Solution::add_two_numbers(list![9,9,9,9,9,9,9], list![9,9,9,9]), list![8,9,9,9,0,0,0,1]);
 }