cin.eof() functionality

Question

I understand that cin.eof() tests the stream format. And while giving input, end of character is not reached when there is wrong in the input. I tested

Answer 1

cin.eof() test if the stream has reached end of file which happens if you type something like Ctrl+C (on Windows), or if input has been redirected to a file etc.

To test if the input contains an integer and nothing but an integer, you can get input first into a string and then convert that with a stringstream. A stringstream indeed reaches eof if there's no more to be extracted from it.

#include 
#include 
#include 

int main() {
    using namespace std;
    int i;
    string input;
    cin >> input; //or getline(cin, input)
    stringstream ss(input);
    if (ss >> i && ss.eof()) {  //if conversion succeeds and there's no more to get
        cout<< "\n Correct Input \n";
    }
    else {
        cout<< "\n Format Error \n";
    }

  return 0;
}