Find a string within a string

findstr.cpp

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

using namespace std;

int main()
{
    string string1, string2;
    int pos = -1;
    vector<int> positions;
    vector<int>::iterator itr;

    cout << "Enter a string: \n";
    getline(cin, string1);

    cout << "\nEnter a string to find: \n";
    getline(cin, string2);

    for(;;)
    {
        pos = string1.find(string2, pos+1);
        if (pos != string::npos)
            positions.push_back(pos+1); // store position in list
        else
            break;
    }

    if (!positions.empty())
    {
        cout << "\nString found at position/s: ";
        for(itr=positions.begin(); itr < positions.end(); itr++)
            cout << *itr << " "; // print positions
    }
    else
        cout << "\nString not found.";

    cout << endl;

    return 0;
}