add: rust reverse list

rust/json/.gitignore

@@ -0,0 +1 @@
+target

rust/list/.gitignore

@@ -0,0 +1 @@
+target

rust/list/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "list"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

rust/list/src/main.rs

@@ -0,0 +1,103 @@
+
+
+// Definition for singly-linked list.
+#[derive(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
+    }
+  }
+}
+
+struct Solution();
+impl Solution {
+    pub fn swap_pairs(head: Option<Box<ListNode>>) -> Option<Box<ListNode>> {
+		let mut cur = head?;
+		if let Some(mut next) = cur.next {
+			cur.next = Solution::swap_pairs(next.next);
+			next.next = Some(cur);
+			return Some(next)
+		}
+		Some(cur)
+    }
+
+
+	pub fn reverse_between(head: Option<Box<ListNode>>, left: i32, right: i32) -> Option<Box<ListNode>> {
+
+		let mut head = head;
+		let mut left_prev_node = &mut head;
+		for _ in 0..left-2{
+			left_prev_node = &mut left_prev_node.as_mut().unwrap().next;
+		}
+		let mut left_prev_node_ptr = left_prev_node.as_mut().unwrap();
+		// if let Some(left_node_ptr) = left_node {
+			left_prev_node_ptr.next = Solution::reverse(left_prev_node_ptr.next.take());
+		// }
+
+		head
+
+    }
+
+
+
+	pub fn _reverse(prev: Option<Box<ListNode>>, cur: Option<Box<ListNode>>) -> Option<Box<ListNode>> {
+		let mut cur_node = cur?;
+		let next = cur_node.next;
+		cur_node.next = prev;
+		if next.is_none() {
+			return Some(cur_node);
+		}
+		Solution::_reverse(Some(cur_node), next)
+	}
+
+	pub fn reverse(head: Option<Box<ListNode>>) -> Option<Box<ListNode>> {
+		Solution::_reverse(None, head)
+	}
+
+
+	pub fn print_list(head: &Option<Box<ListNode>>) {
+		let mut cur = head;
+		while let Some(cur_ptr) = cur {
+			print!("{} ",cur_ptr.val);
+			cur = &cur_ptr.next;
+		}
+		println!()
+	}
+}
+
+fn main() {
+	// let list = None;
+	let list = Some(Box::new(ListNode{
+		val: 1,
+		// next: None,
+		next: Some(Box::new(ListNode{
+			val:2,
+			next: Some(Box::new(ListNode{
+				val:3,
+				// next: None,
+				next:Some(Box::new(ListNode{
+					val:4,
+					next: Some(Box::new(ListNode{
+						val: 5,
+						next: None
+					}))
+				}))
+			}))
+		}))
+	}));
+
+	Solution::print_list(&list);
+	let new_list = Solution::reverse_between(list, 2,4);
+	Solution::print_list(&new_list);
+
+
+
+}