solves #2465: Number of Distinct Averages in java

Author: anishLearnsToCode

Diff for: README.md

@@ -778,7 +778,7 @@
 | 2451 | [Odd String Difference](https://leetcode.com/problems/odd-string-difference)                                                                                           |                                                                                     [![Java](assets/java.png)](src/OddStringDifference.java)                                                                                     |                                                                                                                                   |
 | 2455 | [Average Value of Even Numbers That Are Divisible by Three](https://leetcode.com/problems/average-value-of-even-numbers-that-are-divisible-by-three)                   |                                                                      [![Java](assets/java.png)](src/AverageValueOfEvenNumbersThatAreDivisibleByThree.java)                                                                       |                                                                                                                                   |
 | 2460 | [Apply Operations to an Array](https://leetcode.com/problems/apply-operations-to-an-array)                                                                             |                                                                                  [![Java](assets/java.png)](src/ApplyOperationsToAnArray.java)                                                                                   |                                                                                                                                   |
-| 2465 | [Number of Distinct Averages](https://leetcode.com/problems/number-of-distinct-averages)                                                                               |                                                                                                                                                                                                                                  |                                                                                                                                   |
+| 2465 | [Number of Distinct Averages](https://leetcode.com/problems/number-of-distinct-averages)                                                                               |                                                                                  [![Java](assets/java.png)](src/NumberOfDistinctAverages.java)                                                                                   |                                                                                                                                   |
 | 2466 | [Count Ways To Build Good Strings](https://leetcode.com/problems/count-ways-to-build-good-strings)                                                                     |                                                                                                                                                                                                                                  |                                                                                                                                   |
 | 2475 | [Number of Unequal Triplets in Array](https://leetcode.com/problems/number-of-unequal-triplets-in-array)                                                               |                                                                                                                                                                                                                                  |                                                                                                                                   |
 | 2481 | [Minimum Cuts to Divide a Circle](https://leetcode.com/problems/minimum-cuts-to-divide-a-circle)                                                                       |                                                                                                                                                                                                                                  |                                                                                                                                   |

Diff for: src/NumberOfDistinctAverages.java

@@ -0,0 +1,21 @@
+// https://leetcode.com/problems/number-of-distinct-averages
+// T: O(Nlog(N))
+// S: O(N)
+
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Set;
+
+public class NumberOfDistinctAverages {
+    public int distinctAverages(int[] nums) {
+        final Set<Integer> set = new HashSet<>();
+        Arrays.sort(nums);
+
+        for (int i = 0 ; i < nums.length / 2 ; i++) {
+            int sum = nums[i] + nums[nums.length - 1 - i];
+            set.add(sum);
+        }
+
+        return set.size();
+    }
+}