how to get check two conditions for one input? C++

so basically when an input is entered it has to be against two conditions. if its exit terminate the while loop immediately and if the a copy of the input exists in the input1(which is a map) only then save it in the finallist(map). if such input is entered which doesnt exists in input1. the user should be asked again to enter something else. this what i have so far. for exit and for other inputs its working fine. when i enter a valid input it still says "this item is not in the section..." can someone please help. what conditionw should i put to make this work.
cout << "enter the items you want to buy. press exit to proceed" <> a; int choice;

LOOP:       while(select1    !=     "exit")
  {
            for(it    =   input1.begin();      it   !=   input1.end();     ++it)
      {
 if(it    ->      first !=     a)   continue;
 {
 choice=      input1[select1];
 finallist[a]    =       choice;
        cout <<  "you bought "   <<   a   <<  " for price "<< finallist[a]<<endl;
        spentmoney(choice); //calculate prices
        cin      >>      a;
        if(select1 == "exit")
         {
         goto LOOP;
         } 
        choice      =       input1[a];
        finallist[a]    =    choice;
        cout <<      "you bought "<<a <<" for price<<  finallist[a}<<endl;
    spentmoney(choice);           
       }
     }
cout<< "This Item is not available in the section you are in"      <<       endl;
cout       <<  "Buy something else"<<      endl;
cin      >>      a;

 if(a     ==    "exit")
    {
      goto LOOP;
    }

}