diff --git a/0287-find-the-duplicate-number/0287-find-the-duplicate-number.cpp b/0287-find-the-duplicate-number/0287-find-the-duplicate-number.cpp
new file mode 100644
index 0000000..e64b302
--- /dev/null
+++ b/0287-find-the-duplicate-number/0287-find-the-duplicate-number.cpp
@@ -0,0 +1,13 @@
+class Solution {
+public:
+    int findDuplicate(vector<int>& nums) {
+        long long n = nums.size();
+        sort(nums.begin(), nums.end());
+        for (int i = 0; i < n; i++) {
+            if (nums[i] == nums[i + 1]) {
+                return nums[i];
+            }
+        }
+        return {};
+    }
+};
\ No newline at end of file