diff --git a/Algorithms/Medium/287_FindTheDuplicateNumber/Solution.cpp b/Algorithms/Medium/287_FindTheDuplicateNumber/Solution.cpp
new file mode 100644
index 0000000..6929d73
--- /dev/null
+++ b/Algorithms/Medium/287_FindTheDuplicateNumber/Solution.cpp
@@ -0,0 +1,16 @@
+class Solution {
+public:
+    int findDuplicate(vector<int>& nums) {
+        sort(nums.begin(), nums.end());
+        int n = nums.size();
+        for (int i = 0; i < n-1; i++)
+        {
+            if(nums[i] == nums[i+1])
+                return nums[i];
+        }
+        return -1;
+    }
+};
+
+// Time Complexity: O(nlogn)
+// Space Complexity: O(n)