I figured it out..
std::string path(1.2.3);
int number;
std::stringstream ss(path);
while (!ss.eof()) {
if (ss.peek() != '.') {
ss >> number;
if (ss.tellg() == -1) {
std::cout << "Last one: " << number;
} else {
std::cout << number;
}
} else { ss.get(); }
}