Added files

Author: nullptr

csharp/1929-concatenation-of-array.cs

@@ -0,0 +1,13 @@
+public class Solution {
+    public int[] GetConcatenation(int[] nums) {
+        int n = nums.Length;
+        int[] ans = new int[2 * n];
+        
+        for (int i = 0; i < n; i++) {
+            ans[i] = nums[i];
+            ans[i + n] = nums[i];
+        }
+        
+        return ans;
+    }
+}