#include <string>
#include <vector>
#include <iostream>
#include <cstring>
using namespace std;

int main() {
vector<size_t> v;
v.push_back(1);
v.push_back(2);
v.push_back(3);

string s((char*)(&v[0]), 3 * sizeof(size_t));

vector<size_t> w(3);
strncpy((char*)(&w[0]), s.c_str(), 3 * sizeof(size_t));

for (size_t i = 0; i < w.size(); ++i) {
    cout << w[i] << endl;
}
}