Using cin.bad() to check for integer [duplicate]

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• Why would we call cin.clear() and cin.ignore() after reading input? 2 answers

If I type in letters it will just print out "Please enter a positive integer value: Please enter a positive integer value:", it does not allow me to reenter an input.

cout << "Please enter a positive integer value: ";
int num;
cin >> num ;

if(cin.bad() || num <= 0 ) {
    cout << "Please enter a positive integer value: ";
    cin >> num;
}

if(cin.bad() || num <= 0 ) {
    cout << "Please enter a positive integer value: ";
    cin >> num;
}