From 69ad28ca0ecbcd726619d5aad81351d4e275db54 Mon Sep 17 00:00:00 2001
From: fwqaaq <fwqaaq@gmail.com>
Date: Mon, 24 Jul 2023 23:57:57 +0800
Subject: [PATCH 1/2] =?UTF-8?q?Update=200647.=E5=9B=9E=E6=96=87=E5=AD=90?=
 =?UTF-8?q?=E4=B8=B2.md=20about=20rust?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 problems/0647.回文子串.md | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

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">

From 6011184b37f9e1d661edef1b124b5e195ef55bd9 Mon Sep 17 00:00:00 2001
From: fwqaaq <fwqaaq@gmail.com>
Date: Tue, 25 Jul 2023 00:18:19 +0800
Subject: [PATCH 2/2] =?UTF-8?q?Update=200647.=E5=9B=9E=E6=96=87=E5=AD=90?=
 =?UTF-8?q?=E4=B8=B2.md?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 problems/0647.回文子串.md | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/problems/0647.回文子串.md b/problems/0647.回文子串.md
index 35396192..52f12d9b 100644
--- a/problems/0647.回文子串.md
+++ b/problems/0647.回文子串.md
@@ -519,6 +519,24 @@ function expandRange(s: string, left: number, right: number): number {
 
 Rust：
 
+```rust
+impl Solution {
+    pub fn count_substrings(s: String) -> i32 {
+        let mut dp = vec![vec![false; s.len()]; s.len()];
+        let mut res = 0;
+
+        for i in (0..s.len()).rev() {
+            for j in i..s.len() {
+                if s[i..=i] == s[j..=j] && (j - i <= 1 || dp[i + 1][j - 1]) {
+                    dp[i][j] = true;
+                    res += 1;
+                }
+            }
+        }
+        res
+    }
+}
+```
 
 > 双指针