String to Vector

How I can place number from a String value of
S1("4545645486465") to a vector Vec.. The trick part is that I have to place 4 digits in each cell of the vector. Example:

string s1("468648578468486846845")
vector<int>Vec
void main()
{
...
...
...
...

}
Vec[0]=4686
Vec[1}=4857
Vec[2]=8468
....Vec[n]
....
Please Help me..

Think about this logically.
You need to extract 4 characters, get their numerical value, and push them onto a vector.

Code:

---

#include <vector>
#include <string>
#include <iostream>
#include <cstdlib>

std::vector<int> fill_vec(const std::string &input);

int main(int argc, char* argv[])
{
        std::string mystr("13345678198734568765");
        std::vector<int> returned = fill_vec(mystr);

        for (int i = 0; i < returned.size(); i++)
                std::cout<<returned[i]<<std::endl;
        return 0;
}


std::vector<int> fill_vec(const std::string &input)
{
        typedef std::string::size_type st;

        std::string temp;
        std::vector<int> intvec;

        for (st index = 0; index < input.size(); index += 4)
        {
                for (int i = index; i < index+4; i++)
                        temp += input[i];

                intvec.push_back(atoi(temp.c_str()));
                temp.erase();
               
        }
        return intvec;
}

---

It's 3AM
Here's a sloppy, yet functional solution. input must be a multiple of 4.