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How to reset a stringstream object?

I am trying to write code that will take a string of 4 numbers separated by 3 spaces and put them into two integer arrays representing the x and y values of two coordinates. ie:
INPUT:
0 0 4 7

coordinate_1[X] = 0
coordinate_1[Y] = 0
coordinate_2[X] = 4
coordinate_2[Y] = 7

Here is the code:

#include <iostream>

#include <string>

#include <sstream>

#include <stdlib.h>



using namespace std;



int main()

{

    int cor_1[2];

    int cor_2[2];

    

    string input;

    string temp;

    

    stringstream StrToInt;

    

    getline(cin, input);

    

    StrToInt << input[0];

    StrToInt >> cor_1[0];

    

    StrToInt << input[2];

    StrToInt >> cor_1[1];

    

    StrToInt << input[4];

    StrToInt >> cor_2[0];

    

    StrToInt << input[6];

    StrToInt >> cor_1[1];



    cout << cor_1[0] << cor_1[1] << cor_2[0] << cor_2[1] << "\n";

    

    system("PAUSE");

    

    return 0;

    

}

I figured that I could add x to the stream, read x from the stream, add y to the stream, read y from the stream etc. The output for the program is incorrect though, the only correct value ends up being cor_1[0]. All the others seem to be random numbers of great length.
What is it about the above code or my understanding of stringstreams that is wrong?

Your first transaction exausts the stream and sets the eof bit. That's a sort of fail condition. The stream won't work again for you until you clear that. Here are two good suggestions: 1) read the documentation for the things you use; 2) always test for success when you use those things. Failure is not an uncommon occurrence, particularly when a user is involved.

I forgot to mention that I had tried StrToInt.clear(), then StrToInt.str("") after it was read. It did not change the result :confused: .
I am not very experienced in c++ and many guides on the STL are confusing. Unfortunately I have a programming competition this Tuesday and I have to focus on concepts, not semantics, although I recognize that normally its good to focus on both.
I'll keep looking for some info, and as always thanks for the quick reply DaWei.

Unfortunately, the value of a concept is sometimes -858993460 ;).

I tried messing around with the code again and it turns out using StrToInt.clear() works after all. Must have been a typo somewhere in the code.

What do you mean by "documentation"? Is there something like unix 'man' pages for c++ libraries? The library, google and programmingfourms are the only "documentation" I use right now.

Man pages are good. I sometimes use them. I also use MSDN on line, and have an ancient set of MSDN CDs tied into my help system. In particular, research the >> operator.

Realize that any function that is asked to convert user input to numeric values is wide open for trouble. %x*zh is hard to convert. Users may be inattentive, malicious, unknowing, or merely fall asleep with their forehead on the keyboard. Failing to test operations for success is the hallmark of a novice, at best. It could represent actionable negligence.

As far as C++ documentation goes, the SGI Standard Template Library Programmer's Guide is about as good as I have found for free online. It is similar to unix man pages for each item in the library.