Question

I can’t understand why does vector empty after it’s filling.

The code is:

bool fillArray (vector<int> &array)
{        
    string temp;
    getline(cin, temp);

    if (temp  == "-1")
       return false
    else
       return true;

    int res = atoi(temp.c_str());
    array.push_back(res);
}

void showArray(const vector<int> array)
{
    for (int i = 0; i < array.size(); i ++)
        cout << array[i] << " ";
}


int main(int argc, char** argv)
{
    vector<int> array;

    while (fullArray (array))
    {}

    showArray(array);
    return 0;
}

When I input -1 the cycle breaks but the size of vector is 0, why?

Answer 1

These lines are your problem:

    if (temp  == "-1")
       return false
    else
       return true;

    int res = atoi(temp.c_str());
    array.push_back(res);

In the case of good input, you’re returning true from your fillArray method before you actually call push_back with the value on your vector.