feat: add rust solution to lc problem: No.3583

Author: yanglbme

solution/3500-3599/3583.Count Special Triplets/README.md

@@ -239,6 +239,43 @@ function specialTriplets(nums: number[]): number {
 }
 ```
 
+#### Rust
+
+```rust
+use std::collections::HashMap;
+
+impl Solution {
+    pub fn special_triplets(nums: Vec<i32>) -> i32 {
+        let mut left: HashMap<i32, i64> = HashMap::new();
+        let mut right: HashMap<i32, i64> = HashMap::new();
+
+        for &x in &nums {
+            *right.entry(x).or_insert(0) += 1;
+        }
+
+        let modulo: i64 = 1_000_000_007;
+        let mut ans: i64 = 0;
+
+        for &x in &nums {
+            if let Some(v) = right.get_mut(&x) {
+                *v -= 1;
+            }
+
+            let t = x * 2;
+
+            let l = *left.get(&t).unwrap_or(&0);
+            let r = *right.get(&t).unwrap_or(&0);
+
+            ans = (ans + (l * r) % modulo) % modulo;
+
+            *left.entry(x).or_insert(0) += 1;
+        }
+
+        ans as i32
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->

solution/3500-3599/3583.Count Special Triplets/README_EN.md

@@ -237,6 +237,43 @@ function specialTriplets(nums: number[]): number {
 }
 ```
 
+#### Rust
+
+```rust
+use std::collections::HashMap;
+
+impl Solution {
+    pub fn special_triplets(nums: Vec<i32>) -> i32 {
+        let mut left: HashMap<i32, i64> = HashMap::new();
+        let mut right: HashMap<i32, i64> = HashMap::new();
+
+        for &x in &nums {
+            *right.entry(x).or_insert(0) += 1;
+        }
+
+        let modulo: i64 = 1_000_000_007;
+        let mut ans: i64 = 0;
+
+        for &x in &nums {
+            if let Some(v) = right.get_mut(&x) {
+                *v -= 1;
+            }
+
+            let t = x * 2;
+
+            let l = *left.get(&t).unwrap_or(&0);
+            let r = *right.get(&t).unwrap_or(&0);
+
+            ans = (ans + (l * r) % modulo) % modulo;
+
+            *left.entry(x).or_insert(0) += 1;
+        }
+
+        ans as i32
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->

solution/3500-3599/3583.Count Special Triplets/Solution.rs

@@ -0,0 +1,32 @@
+use std::collections::HashMap;
+
+impl Solution {
+    pub fn special_triplets(nums: Vec<i32>) -> i32 {
+        let mut left: HashMap<i32, i64> = HashMap::new();
+        let mut right: HashMap<i32, i64> = HashMap::new();
+
+        for &x in &nums {
+            *right.entry(x).or_insert(0) += 1;
+        }
+
+        let modulo: i64 = 1_000_000_007;
+        let mut ans: i64 = 0;
+
+        for &x in &nums {
+            if let Some(v) = right.get_mut(&x) {
+                *v -= 1;
+            }
+
+            let t = x * 2;
+
+            let l = *left.get(&t).unwrap_or(&0);
+            let r = *right.get(&t).unwrap_or(&0);
+
+            ans = (ans + (l * r) % modulo) % modulo;
+
+            *left.entry(x).or_insert(0) += 1;
+        }
+
+        ans as i32
+    }
+}