This program prints a specified amount of numbers within a specified range. However, when I enter a character, it just endlessly loops whichever do-while loop I do it in. E.
You could try doing something like
int a;
string trash;
do {
cout << "Enter minimum number" << endl;
cin >> a;
if(cin.fail()){
cin.clear();
cin >> trash;
}
} while (cin.fail());
This will remove any bad input from the cin stream by throwing it into the trash string.
This link may help you understand these cin functions a bit better.
http://web.eecs.utk.edu/~cs102/lectures/cinLecture.html