Infinite loop with cin when typing string while a number is expected

Question

In the following loop, if we type characters as the cin input instead of numbers which are expected, then it goes into infinite loop. Could anyone please explai

Answer 1

Another alternative is operator! ,it is equivalent to member function fail()

//from Doug's answer
if ( !cin )
{
   cout << "ERROR -- You did not enter an integer";

   // get rid of failure state
   cin.clear(); 

   // From Eric's answer (thanks Eric)
   // discard 'bad' character(s) 
   cin.ignore(std::numeric_limits::max(), '\n');
}