feat: add rust solution to lc problem: No.0022 (doocs#1252)

Author: xzhseh

solution/0000-0099/0022.Generate Parentheses/README.md

@@ -219,6 +219,37 @@ impl Solution {
 }
 ```
 
+```rust
+impl Solution {
+    pub fn generate_parenthesis(n: i32) -> Vec<String> {
+        let mut dp: Vec<Vec<String>> = vec![vec![]; n as usize + 1];
+
+        // Initialize the dp vector
+        dp[0].push(String::from(""));
+        dp[1].push(String::from("()"));
+
+        // Begin the actual dp process
+        for i in 2..=n as usize {
+            for j in 0..i as usize {
+                let dp_c = dp.clone();
+                let first_half = &dp_c[j];
+                let second_half = &dp_c[i - j - 1];
+
+                for f in first_half {
+                    for s in second_half {
+                        let f_c = f.clone();
+                        let cur_str = f_c + "(" + &*s + ")";
+                        dp[i].push(cur_str);
+                    }
+                }
+            }
+        }
+
+        dp[n as usize].clone()
+    }
+}
+```
+
 ### **...**
 
 ```

solution/0000-0099/0022.Generate Parentheses/README_EN.md

@@ -191,6 +191,37 @@ impl Solution {
 }
 ```
 
+```rust
+impl Solution {
+    pub fn generate_parenthesis(n: i32) -> Vec<String> {
+        let mut dp: Vec<Vec<String>> = vec![vec![]; n as usize + 1];
+
+        // Initialize the dp vector
+        dp[0].push(String::from(""));
+        dp[1].push(String::from("()"));
+
+        // Begin the actual dp process
+        for i in 2..=n as usize {
+            for j in 0..i as usize {
+                let dp_c = dp.clone();
+                let first_half = &dp_c[j];
+                let second_half = &dp_c[i - j - 1];
+
+                for f in first_half {
+                    for s in second_half {
+                        let f_c = f.clone();
+                        let cur_str = f_c + "(" + &*s + ")";
+                        dp[i].push(cur_str);
+                    }
+                }
+            }
+        }
+
+        dp[n as usize].clone()
+    }
+}
+```
+
 ### **...**
 
 ```