C++ user input restriction with proper retry without “goto”

Question

I have the following code:

qstn:
  cout << \"Input customer\'s lastname: \";
  getline(cin, lname);

  if (lname.find_first_not_of(\"abcdefghijklmnopqr         


        

Answer 1

A While loop looks like your best bet. You can redo the loop with the continue keyword.

int incorrect = 0;
while(!incorrect) {
cout<<"Input customer's lastname: ";
        getline(cin,lname);

        if(lname.find_first_not_of("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ ")!=string::npos)
            {
            cout<<"You can only input alpha here!\n";
            cin.clear();
            continue;
            }
        else if(lname.empty())
        {
            cout<<"Please enter your firstname!\n";
            cin.clear();
            continue;
        }
        int lnamel=lname.length();
        int strl=str.length();
        int is=0;
        for(int i=1; i