feat: add rust solution to lc problem: No.2441 (doocs#1364)

Signed-off-by: xiaolatiao <1628652790@qq.com>

Author: dierbei

solution/2400-2499/2441.Largest Positive Integer That Exists With Its Negative/README.md

@@ -164,6 +164,29 @@ impl Solution {
 }
 ```
 
+```rust
+use std::collections::HashSet;
+
+impl Solution {
+    pub fn find_max_k(nums: Vec<i32>) -> i32 {
+        let mut ans = -1;
+        let mut h = HashSet::new();
+
+        for &n in &nums {
+            h.insert(n);
+        }
+
+        for &n in &nums {
+            if h.contains(&-n) && n > ans {
+                ans = n;
+            }
+        }
+
+        ans
+    }
+}
+```
+
 ### **...**
 
 ```

solution/2400-2499/2441.Largest Positive Integer That Exists With Its Negative/README_EN.md

@@ -144,6 +144,29 @@ impl Solution {
 }
 ```
 
+```rust
+use std::collections::HashSet;
+
+impl Solution {
+    pub fn find_max_k(nums: Vec<i32>) -> i32 {
+        let mut ans = -1;
+        let mut h = HashSet::new();
+
+        for &n in &nums {
+            h.insert(n);
+        }
+
+        for &n in &nums {
+            if h.contains(&-n) && n > ans {
+                ans = n;
+            }
+        }
+
+        ans
+    }
+}
+```
+
 ### **...**
 
 ```