how to accept only whole numbers in c++ -

i new programming , need term project. have made program simulates hotel booking, problem whenever non-whole number entered first question, goes infinite loop. if second question , enter non-whole number accepts whole number dropping off comes after decimal , skips next question , stops running program.

    #include <iostream>     #include <string>     using namespace std;  int stay_length (int stay)  {          int nights = stay;     int total = 0*nights;     return total; }  int rooms_booking(int rooms) {     int rooms_booked = rooms;     int total = 0;      if(rooms_booked > 0)      {         total = rooms_booked * 50;      }     else     {         total = 0;     }        return total; }  int main(){     int x;     string repeat;     int nights;     int total = 0;       int rooms_avail = 10;     int rooms;      cout << "hello! welcome hotel comp 150." << endl;     {         if (rooms_avail > 0) {          cout << "how many nights staying?" << endl;      }     else {         cout << "sorry, there no rooms available. " << endl;     }          {          cin >> nights;               if (nights > 0 && nights <= 28)             {                 int total1 = stay_length(nights);                 cout << "you staying " << nights << " nights" << endl;                 cout << "that costs: $" << total1 << endl;                 total = total + total1;             }             else             {             cout << "you cannot stay less 1 or more 28 nights" << endl;             }           } while (nights <= 0 || nights >28);              if (rooms_avail > 0)             {                 cout << "how many rooms booking?" << endl;                     cout << "there " << rooms_avail << " available." << endl;                     cin >> rooms;                      if (rooms > 0 && rooms <= rooms_avail)                     {                          int total2 = rooms_booking(rooms);                         cout << "you booking " << rooms << " rooms." << endl;                         cout << "that costs : $" << total2 << endl;                         total = total + total2;                         rooms_avail = rooms_avail - rooms;                     }                     else if (rooms <= 0 || rooms > rooms_avail)                     {                         do{                             cout << "you can book minimum of 1 room or maximum of " << rooms_avail << endl;                             cin >> rooms;                           } while (rooms <= 0 || rooms > rooms_avail );                           int total2 = rooms_booking(rooms);                           cout << "you booking " << rooms << " rooms." << endl;                           cout << "that costs : $" << total2 << endl;                           total = total + total2;                           rooms_avail = rooms_avail - rooms;                      }                     else                     {                      cout << "you cannot book more " << rooms_avail << endl;                     }               }               else              {                 cout << "sorry, rooms have been booked." << endl;              }     cout << "your total far is: $" << total << endl;     cout << "would make booking? enter 'y' or 'y' so."  << endl;     cin >> repeat;           }while(repeat == "y" || repeat == "y");     return 0; } 

it's better use std::getline() instead of operator>> read interactive input std::cin.

operator>> not reading single line of text standard input, , storing it. that's std::getline() for.

if wrong kind of input entered, not operator>> expects, sets std::cin failed state, makes future attempts read std::cin fail, resulting in infinite loop observing.

to correctly, going either:

1) check fail() after every operator>>, see if input failed, if recover error clear(), ignore(). gets real old, quickly.

2) it's easier read single line of text std::getline(), parse input yourself. construct std::istringstream, if wish, , use operator>> that, if makes easier you.