STL sort failure

[Elidor]

Could someone please tell me why the STL sort method in this program aborts the program.

#include <iostream>
#include <cstdlib>
#include <ctime>
#include <vector>
#include <list>
#include <algorithm>

int main()
{
	using namespace std;
	
	srand(time(NULL));
	int vector_size;
	
	cout << "How many numbers would you like for this test? ";
	cin >> vector_size;
	
	vector<int> vi0, vi;
	list<int> li;
	
	for (int i = 0; i < vector_size; i++)
		vi0.push_back(rand() % 100 + 1);
	
	vi = vi0;
	copy(vi0.begin(), vi0.end(), li.begin());
	
	clock_t start = clock();
	sort(vi.begin(), vi.end());
	clock_t end = clock();
	cout << "vi0 sort time: " << (double)(end - start)/CLOCKS_PER_SEC << endl;

	start = clock();
	li.sort();
	end = clock();
	cout << "li sort time: " << (double)(end - start)/CLOCKS_PER_SEC << endl;
	
	return 0;
}

[JLBorges]

        // ...
	vector<int> vi0, vi;
	list<int> li;
	
	for (int i = 0; i < vector_size; i++)
		vi0.push_back(rand() % 100 + 1);
	
	vi = vi0;

	// *** error; list li is empty; leads to undefined behaviour
	copy(vi0.begin(), vi0.end(), li.begin());  // *** 
       // ...
       // undefined behaviour 

[Elidor]

Thank you, I'm sorry for the newbie question. I've substituted it with this now but if anyone can tell me if there is a more efficient way of coding this it would be greatly appreciated.

for (int i = 0; i < vector_size; i++)
		li.push_back(vi0[i]); 

[JLBorges]

Slightlty more efficient:

vector<int> vi0, vi;
list<int> li;
// push_back etc ...
li.assign( vi0.begin(), vi0.end() ) ;

Or better, don't define li till we know how to initialize it:

vector<int> vi0, vi;
// push_back etc ...
list<int>li( vi0.begin(), vi0.end() ) ;

[Elidor]

Once again thank you for the help. Unfortunately I wasn't aware/overlooked the fact you can initialize those containers through iterator ranges.