#include <iostream>
#include <vector>
#include <string>
 
using namespace std;
 
 
int main() {
 
	vector<string> arr;
 
	arr.push_back("one");
	arr.push_back("two");
	arr.push_back("three");
 
	auto& x = arr[2];
 
	cout << "addr x: " << &x << endl; 
 
	/*
	for (int i=0; i<1000; ++i) {
        arr.push_back("num: " + i);
    }*/
 
    cout << "addr x: " << &x << endl; 
 
    auto& x2 = arr[2];
 
 
    cout << "addr x2: " << &x2 << endl; 
 
    cout << x << endl; // segfault arr had been reallocated x points to freed memory
 
	return 0;
}

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