feat: add rust solution to lc problem: No.1281

No.1281.Subtract the Product and Sum of Digits of an Integer

Author: YangFong

solution/1200-1299/1281.Subtract the Product and Sum of Digits of an Integer/README.md

@@ -112,6 +112,24 @@ func subtractProductAndSum(n int) int {
 }
 ```
 
+### **Rust**
+
+```rust
+impl Solution {
+    pub fn subtract_product_and_sum(mut n: i32) -> i32 {
+        let mut mul = 1;
+        let mut sum = 0;
+        while n != 0 {
+            let num = n % 10;
+            n /= 10;
+            mul *= num;
+            sum += num;
+        }
+        mul - sum
+    }
+}
+```
+
 ### **...**
 
 ```

solution/1200-1299/1281.Subtract the Product and Sum of Digits of an Integer/README_EN.md

@@ -104,6 +104,24 @@ func subtractProductAndSum(n int) int {
 }
 ```
 
+### **Rust**
+
+```rust
+impl Solution {
+    pub fn subtract_product_and_sum(mut n: i32) -> i32 {
+        let mut mul = 1;
+        let mut sum = 0;
+        while n != 0 {
+            let num = n % 10;
+            n /= 10;
+            mul *= num;
+            sum += num;
+        }
+        mul - sum
+    }
+}
+```
+
 ### **...**
 
 ```

solution/1200-1299/1281.Subtract the Product and Sum of Digits of an Integer/Solution.rs

@@ -0,0 +1,13 @@
+impl Solution {
+    pub fn subtract_product_and_sum(mut n: i32) -> i32 {
+        let mut mul = 1;
+        let mut sum = 0;
+        while n != 0 {
+            let num = n % 10;
+            n /= 10;
+            mul *= num;
+            sum += num;
+        }
+        mul - sum
+    }
+}