Learning sepples

Hey, /prog/.
I'm a C programmer trying to learn sepples.
Can anybody tell me what is happening in this code?
Why does it go into infinite loop mode if I give a non-integer and how to defend against this?

#include<iostream>
using namespace::std;

int main(){
while(true){
//Why does this sperg out if I put a bad integer in?
int answer = -1;
cin >> answer;
cout << answer << "\n";
}
}


>>1

Why does it go into infinite loop mode if I give a non-integer and how to defend against this?

It's shit.

http://en.cppreference.com/w/cpp/io/basic_ios/fail