Added solution for 2161

Author: chirag64

02161. Partition Array According to Given Pivot.rs

@@ -0,0 +1,20 @@
+impl Solution {
+    // Create 3 vectors: one containing values less than pivot, another equal to pivot and third containing values greater than pivot. Then return all 3 vectors concatenated as a single vector
+    pub fn pivot_array(nums: Vec<i32>, pivot: i32) -> Vec<i32> {
+        let mut less_than_pivot = Vec::new();
+        let mut equal_to_pivot = Vec::new();
+        let mut more_than_pivot = Vec::new();
+        for num in nums {
+            if num < pivot {
+                less_than_pivot.push(num);
+            } else if num > pivot {
+                more_than_pivot.push(num);
+            } else {
+                equal_to_pivot.push(num);
+            }
+        }
+        less_than_pivot.extend(equal_to_pivot);
+        less_than_pivot.extend(more_than_pivot);
+        return less_than_pivot;
+    }
+}