feat: add rust solution to lc problem: No.1971 (#1131)

Author: xzhseh

solution/1900-1999/1971.Find if Path Exists in Graph/README.md

@@ -326,6 +326,39 @@ public:
 };
 ```
 
+### **Rust**
+
+```rust
+impl Solution {
+    pub fn valid_path(n: i32, edges: Vec<Vec<i32>>, source: i32, destination: i32) -> bool {
+        let mut disjoint_set: Vec<i32> = vec![0; n as usize];
+        // Initialize the set
+        for i in 0..n {
+            disjoint_set[i as usize] = i;
+        }
+
+        // Traverse the edges
+        for p_vec in &edges {
+            let parent_one = Solution::find(p_vec[0], &mut disjoint_set);
+            let parent_two = Solution::find(p_vec[1], &mut disjoint_set);
+            disjoint_set[parent_one as usize] = parent_two;
+        }
+
+        let p_s = Solution::find(source, &mut disjoint_set);
+        let p_d = Solution::find(destination, &mut disjoint_set);
+
+        p_s == p_d
+    }
+
+    pub fn find(x: i32, d_set: &mut Vec<i32>) -> i32 {
+        if d_set[x as usize] != x {
+            d_set[x as usize] = Solution::find(d_set[x as usize], d_set);
+        }
+        d_set[x as usize]
+    }
+}
+```
+
 ### **Go**
 
 ```go

solution/1900-1999/1971.Find if Path Exists in Graph/README_EN.md

@@ -189,6 +189,39 @@ public:
 };
 ```
 
+### **Rust**
+
+```rust
+impl Solution {
+    pub fn valid_path(n: i32, edges: Vec<Vec<i32>>, source: i32, destination: i32) -> bool {
+        let mut disjoint_set: Vec<i32> = vec![0; n as usize];
+        // Initialize the set
+        for i in 0..n {
+            disjoint_set[i as usize] = i;
+        }
+
+        // Traverse the edges
+        for p_vec in &edges {
+            let parent_one = Solution::find(p_vec[0], &mut disjoint_set);
+            let parent_two = Solution::find(p_vec[1], &mut disjoint_set);
+            disjoint_set[parent_one as usize] = parent_two;
+        }
+
+        let p_s = Solution::find(source, &mut disjoint_set);
+        let p_d = Solution::find(destination, &mut disjoint_set);
+
+        p_s == p_d
+    }
+
+    pub fn find(x: i32, d_set: &mut Vec<i32>) -> i32 {
+        if d_set[x as usize] != x {
+            d_set[x as usize] = Solution::find(d_set[x as usize], d_set);
+        }
+        d_set[x as usize]
+    }
+}
+```
+
 ### **Go**
 
 ```go

solution/1900-1999/1971.Find if Path Exists in Graph/Solution.rs

@@ -0,0 +1,28 @@
+impl Solution {
+    pub fn valid_path(n: i32, edges: Vec<Vec<i32>>, source: i32, destination: i32) -> bool {
+        let mut disjoint_set: Vec<i32> = vec![0; n as usize];
+        // Initialize the set
+        for i in 0..n {
+            disjoint_set[i as usize] = i;
+        }
+
+        // Traverse the edges
+        for p_vec in &edges {
+            let parent_one = Solution::find(p_vec[0], &mut disjoint_set);
+            let parent_two = Solution::find(p_vec[1], &mut disjoint_set);
+            disjoint_set[parent_one as usize] = parent_two;
+        }
+
+        let p_s = Solution::find(source, &mut disjoint_set);
+        let p_d = Solution::find(destination, &mut disjoint_set);
+
+        p_s == p_d
+    }
+
+    pub fn find(x: i32, d_set: &mut Vec<i32>) -> i32 {
+        if d_set[x as usize] != x {
+            d_set[x as usize] = Solution::find(d_set[x as usize], d_set);
+        }
+        d_set[x as usize]
+    }
+}