fail 28 29 in c 2b 2b

1#include <iostream>
2using namespace std;
3
4int main()
5{
6    int number;
7    do{
8        cin >> number;
9        if(cin.fail())
10            cout << "Not a number " << endl;
11    }while(!cin.fail());
12    cout << "number is " << number << endl;
13    system("pause");
14    return 0;
15}