If the elements push back in the vector are valid?

Hi,

the elements that you inserted in the add() function will be valid after the function add() ends. It is because, the vector is a local variable of the main() function and in the add() function you only reference it.

For this reason, you can write all the elements to the console just after the add() call:

#include<vector>
#include<iostream>
#include<stdio.h>
using std::vector;

void add (vector<int> & a )
{
    for(int i=0;i<=9;i++)
        a.push_back(i);
}
 
int main()
{
    vector<int> a;
    add(a);
    
    // write all the lements
    for (vector<int>::iterator it = a.begin(); it != a.end(); it++)
    {
        printf("Element: %d\n", *it);
    }
}

In the moment when the main() function ends The vector <int> a</int> vill stop being valid and all the elements are destroyed. It is because the vector<int> a</int> is a local variable of the main() function.

Hope it helps.

Best regards,
J.K.