diff --git a/Third Maximum Number b/Third Maximum Number
new file mode 100644
index 0000000..27b8ac0
--- /dev/null
+++ b/Third Maximum Number	
@@ -0,0 +1,25 @@
+ int thirdMax(vector<int>& nums) {
+       sort(nums.begin(),nums.end());
+       set<int>s;
+        int n=nums.size();
+        if(n<3)
+        {
+            return nums[n-1];
+        }else{
+            
+            set<int>s;
+            for(int i=n-1;i>=0;i--)
+            {
+           
+                    s.insert(nums[i]);
+                
+                  if(s.find(nums[i])!=s.end()&&s.size()==3)
+                {
+                    return nums[i];
+                }
+                    
+            }
+        }
+      
+        return nums[n-1];
+    }