How to create a vector of complex numbers in c++?

Question

I have two inputs(real and imaginary parts) for n complex numbers. I can't figure out how to store them together in a vector such that i can perform complex calculations with STL complex functions. This is something I tried but Time Limit gets exceeded.

vector<complex<double> > a;
for(i=0;i<d;i++)
{
    int temp;
    cin>>temp;
    real.push_back(temp);
}
for(i=0;i<d;i++)
{
    int temp;
    cin>>temp;
    imag.push_back(temp);
}
for(i=0;i<d;i++)
{
    a.push_back(complex<double>(real[i], imag[i]));
}

Please show us what have you tried, and explain what doesn't work with your solution. — Algirdas Preidžius, Aug 24 '18 at 13:37
[`std::vector>`?](https://en.cppreference.com/w/cpp/numeric/complex) — BoBTFish, Aug 24 '18 at 13:39
It seem the real problem isn't that you don't know what library component to use, but that "Time Limit gets exceeded". Please give a full explanation of what your code is trying to do, and a [mcve] - then we may be able to suggest a more efficient solution. — BoBTFish, Aug 24 '18 at 13:41
there is no obvious reason why this should trigger a time-limit exceeded. My first guess is that the `cin >>` call takes more time then all the rest. I suspect that you exceed the limit somewhere else in code that you dont show here (I doubt that there is a challenge "fill a vector of complex numbers as fast as you can", usually they require you to do also some output ;) — 463035818_is_not_an_ai, Aug 24 '18 at 13:55
just another wild guess: if you try to read more input than is provided, then the `cin >> temp;` will block forever (or until you exceed the time limit, whatever happens first) — 463035818_is_not_an_ai, Aug 24 '18 at 13:57

score 1 · Accepted Answer · answered Aug 24 '18 at 14:08

Here's an example I used:

double real;
double imaginary;
std::vector<std::complex<double> > database;
//...
std::cin >> real;
std::cin >> imaginary;
const std::complex<double> temp(real, imaginary);
database.push_back(temp);

In the above example, I read in the real and imaginary components separately. Next, I create a temporary complex object using the real and imaginary components. Finally, I push_back the value to the database.

How to create a vector of complex numbers in c++?

1 Answers1