diff --git a/codeforces_rollbacks.cpp b/codeforces_rollbacks.cpp
new file mode 100644
index 0000000..85cd7aa
--- /dev/null
+++ b/codeforces_rollbacks.cpp
@@ -0,0 +1,114 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+
+void display(vector <int> temp)
+{
+    int si = temp.size();
+    for (int m=0;m<si;m++)
+    {
+        cout<<temp[m]<<endl;
+    }
+
+};
+
+void distinct(vector <int> new_temp)
+
+{
+    vector <int> new_temp1 = new_temp;
+    sort(new_temp1.begin(),new_temp1.end());
+
+    auto it = unique(new_temp1.begin(), new_temp1.end());
+
+    new_temp1.resize(distance(new_temp1.begin(), it));
+    cout<<new_temp1.size()<<endl;
+
+    // return c;
+};
+
+
+int main()
+{
+    vector <int> main_arr= {};
+    vector <int> copy_arr = {};
+    int q=0;
+    cout<<"NUM OF QUERIES : ";
+    cin>>q;
+
+    for (int i=0;i<q;i++)
+    {
+   
+        string input="";
+        cin>>input;
+        
+        if (input=="?")
+        {
+            distinct(main_arr);
+        
+            // int answer = distinct(main_arr);
+            // cout<<answer<<endl;
+
+        }
+        
+        else if (input== "!")
+        {
+            main_arr = copy_arr;
+           
+
+        }
+
+
+        else
+        {
+            copy_arr=main_arr;
+            long long int test =0;
+            int k=0;
+            int mg=input.size();
+            if (input[0] == '-') k=1;
+            else if (input[0]=='+') k=0;
+
+            for (int kii=0;kii<mg;kii++)
+            {
+
+                 
+        
+                if (input[kii] == '1')test+=pow(10,mg-1-kii)*1;
+                else if (input[kii] == '2')test+=pow(10,mg-1-kii)*2;
+                else if (input[kii] == '3')test+=pow(10,mg-1-kii)*3;
+                else if (input[kii] == '4')test+=pow(10,mg-1-kii)*4;
+                else if (input[kii] == '5')test+=pow(10,mg-1-kii)*5;
+                else if (input[kii] == '6')test+=pow(10,mg-kii)*6;
+                else if (input[kii] == '7')test+=pow(10,mg-1-kii)*7;
+                else if (input[kii] == '8')test+=pow(10,mg-1-kii)*8;
+                else if (input[kii] == '9')test+=pow(10,mg-1-kii)*9;
+                else if (input[kii] == '0') test+=pow(10,mg-1-kii)*0;
+            }
+
+            if (k==1)test*=-1;
+
+
+            if (test>0)
+            {
+                main_arr.push_back(test);
+                
+            }
+
+            else
+            {
+             
+                for (int temporary=0;temporary<abs(test);temporary++)
+                {
+                    main_arr.pop_back();
+                   
+                }
+            }
+
+            
+
+        }
+       
+
+    }
+
+    return 0;
+};