diff --git a/problems/0647.回文子串.md b/problems/0647.回文子串.md
index 084b9f74..35396192 100644
--- a/problems/0647.回文子串.md
+++ b/problems/0647.回文子串.md
@@ -517,8 +517,33 @@ function expandRange(s: string, left: number, right: number): number {
 }
 ```
 
+Rust：
 
 
+> 双指针
+
+```rust
+impl Solution {
+    pub fn count_substrings(s: String) -> i32 {
+        let mut res = 0;
+        for i in 0..s.len() {
+            res += Self::extend(&s, i, i, s.len());
+            res += Self::extend(&s, i, i + 1, s.len());
+        }
+        res
+    }
+
+    fn extend(s: &str, mut i: usize, mut j: usize, len: usize) -> i32 {
+        let mut res = 0;
+        while i < len && j < len && s[i..=i] == s[j..=j] {
+            res += 1;
+            i = i.wrapping_sub(1);
+            j += 1;
+        }
+        res
+    }
+}
+```
 
 <p align="center">
 <a href="https://programmercarl.com/other/kstar.html" target="_blank">