update leetcode

leetcode_rs/problems/p2/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "p2"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]

leetcode_rs/problems/p2/src/main.rs

@@ -0,0 +1,101 @@
+// 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 }
+    }
+}
+
+fn add_two_numbers(l1: Option<Box<ListNode>>, l2: Option<Box<ListNode>>) -> Option<Box<ListNode>> {
+    let mut dummy_head = Box::new(ListNode::new(0));
+    let mut current = &mut dummy_head;
+    let mut p1 = l1.as_ref();
+    let mut p2 = l2.as_ref();
+    let mut carry = 0;
+
+    while p1.is_some() || p2.is_some() || carry != 0 {
+        let val1 = p1.map_or(0, |node| node.val);
+        let val2 = p2.map_or(0, |node| node.val);
+        let sum = val1 + val2 + carry;
+
+        carry = sum / 10;
+        current.next = Some(Box::new(ListNode::new(sum % 10)));
+        current = current.next.as_mut().unwrap();
+
+        p1 = p1.and_then(|node| node.next.as_ref());
+        p2 = p2.and_then(|node| node.next.as_ref());
+    }
+
+    dummy_head.next
+}
+
+fn main() {
+    // 测试用例 1: 342 + 465 = 807
+    let l1 = Some(Box::new(ListNode {
+        val: 2,
+        next: Some(Box::new(ListNode {
+            val: 4,
+            next: Some(Box::new(ListNode { val: 3, next: None })),
+        })),
+    }));
+    let l2 = Some(Box::new(ListNode {
+        val: 5,
+        next: Some(Box::new(ListNode {
+            val: 6,
+            next: Some(Box::new(ListNode { val: 4, next: None })),
+        })),
+    }));
+    let result = add_two_numbers(l1, l2);
+    println!("Test 1: {:?}", result); // 期望: [7, 0, 8]
+
+    // 测试用例 2: 0 + 0 = 0
+    let l1 = Some(Box::new(ListNode::new(0)));
+    let l2 = Some(Box::new(ListNode::new(0)));
+    let result = add_two_numbers(l1, l2);
+    println!("Test 2: {:?}", result); // 期望: [0]
+
+    // 测试用例 3: 99 + 9 = 108 (有进位)
+    let l1 = Some(Box::new(ListNode {
+        val: 9,
+        next: Some(Box::new(ListNode { val: 9, next: None })),
+    }));
+    let l2 = Some(Box::new(ListNode::new(9)));
+    let result = add_two_numbers(l1, l2);
+    println!("Test 3: {:?}", result); // 期望: [8, 0, 1]
+
+    // 测试用例 4: 999 + 1 = 1000 (多位进位)
+    let l1 = Some(Box::new(ListNode {
+        val: 9,
+        next: Some(Box::new(ListNode {
+            val: 9,
+            next: Some(Box::new(ListNode { val: 9, next: None })),
+        })),
+    }));
+    let l2 = Some(Box::new(ListNode::new(1)));
+    let result = add_two_numbers(l1, l2);
+    println!("Test 4: {:?}", result); // 期望: [0, 0, 0, 1]
+
+    // 测试用例 5: 长度不同的链表 12 + 9999 = 10011
+    let l1 = Some(Box::new(ListNode {
+        val: 2,
+        next: Some(Box::new(ListNode { val: 1, next: None })),
+    }));
+    let l2 = Some(Box::new(ListNode {
+        val: 9,
+        next: Some(Box::new(ListNode {
+            val: 9,
+            next: Some(Box::new(ListNode {
+                val: 9,
+                next: Some(Box::new(ListNode { val: 9, next: None })),
+            })),
+        })),
+    }));
+    let result = add_two_numbers(l1, l2);
+    println!("Test 5: {:?}", result); // 期望: [1, 1, 0, 0, 1]
+}