#include <iostream>
#include <sstream>
#include <string>

int main()
{
    std::string s;

    std::cout << "Input a number: ";
    std::getline(std::cin, s);

    std::stringstream ss(s); // construct string stream from existing string data
    int n;

    ss >> n;
    std::cout << "Number was: " << n << '\n';
}