Ignoring the first character while using getline function for inputs in c++

Question

Why taking input using getline in c++ program is automatically ignoring first letter of my input? What should i do to solve this problem?

edit 1: I have used getline in other functions of same program along with cin.ignore() but it is working fine there.

    cout<<"Enter the roll no: ";        
    cin.ignore();
    getline(cin,rollno);
    cout<<"Enter the name of book you want to issue:";  
    cin.ignore();                                       
    getline(cin,input);                 //input= think and row rich
    cout<<"What's the return data";
    cin.ignore();
    getline(cin,input_date);           // input=20-8-2019

    cout<<input<<" "<<input_date<<endl;      //output of inputs = hink and grow rich and 0-8-2019

If i try to take input without cin.ignore() program is not taking any input..

Answer 1

    cout<<"Enter the roll no: ";
    istream& ignore (streamsize n = 1, int delim = EOF);  //by using this line my code starts working properly.
    cin.ignore();
    getline(cin,rollno);
    cout<<"Enter the name of book you want to issue:";
    getline(cin,input);
    cout<<"What's the return data";
    getline(cin,input_date);

The above code is now taking input of rollno,book name and date one by one and not ignoring any character.Thanks everyone for help