C++ Parsing input string to variables

All i need to do is to parse the input string of your full name, into 3 separate names so I can take the first initials of each and print them. Can anyone point me in the right direction?

#include <iostream>
#include <string>
#include <fstream>
#include <iomanip>
using namespace std;    
int main()
{
    string [parsed_output] = fullName.split(" ");
    string firstName = parsed_output[0];
    string middleName = parsed_ouput[1];
    string lastName = parsed_output[2];
    string fullName;
    char firstLetter = firstName[0];
    char middleLetter = middleName[0];
    char lastLetter = lastName[0];
    cout << "Enter your first name, middle name or initial, and last name separated by                              spaces: \n"; 
    cin >> fullName;

    cout << "Your initials are: " << firstLetter << middleLetter << lastLetter << '\n';
    cout << "Your name is: " << firstName << " " << middleName << " " << lastName << '\n';
return 0;
}