using getline() and then extracting strings from user input (using C++) - c++

Question

Hi guys I'm not really understanding how I would separate the users inputs when using getline(). For example the user inputs his birth date and from that I extract the month, date, and year from that.
eg.) for Sunday, January 2, 2010. I have
int main()
{
string inputStream;
string date, month, day, year;
string i;
string j;
getline(cin, inputStream);
//cin >> date >> month >> day >> year;
i = inputStream.substr(0, inputStream.find(","));
j = inputStream.substr(inputStream.find(","), inputStream.find(","));
date = i;
month = j;
cout << month << " " << day << " was a " << date << " in" << year << endl;
return0;
}
For i it works properly and will display sunday but for j it doesn't seem to want to work. Can someone show me where I went wrong? I'm not sure how I would extract the next value after the date.

Answer 1

Following modifications are done in your code to parse the day, date, month and year from the input string (as per your input format) successfully.
#include <iostream>
using namespace std;
int main()
{
string inputStream;
string date, month, day, year;
string i;
string j;
getline(cin, inputStream);
// day
day = inputStream.substr(0, inputStream.find(","));
// month
int pos1 = inputStream.find(",") + 2; // Go ahead by 2 to ignore ',' and ' ' (space)
int pos2 = inputStream.find(" ", pos1); // Find position of ' ' occurring after pos1
month = inputStream.substr(pos1, pos2-pos1); // length to copy = pos2-pos1
// date
int pos3 = inputStream.find(",", pos2); // Find position of ',' occurring after pos2
date = inputStream.substr(pos2, pos3-pos2); // length to copy = pos3-pos2
// year
year = inputStream.substr(pos3+2); // Go ahead by 2 to ignore ',' and ' ' (space)
cout << "day = " << day << endl;
cout << "date = " << date << endl;
cout << "month = " << month << endl;
cout << "year = " << year << endl;
return 0;
}
Hope this helps you.