Visual Studio C++ How do I RNG multiple times & sum the results [duplicate]

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• Generate random numbers using C++11 random library 4 answers

I'm using Microsoft Visual Studio C++ 2017

I'm fairly new to coding, and for one of my first projects I'm taking on making a dice software to simulate rolling dice. I've got all the code I need to roll one dice. But one thing I'm having trouble finding an answer to is how can I have the user input a variable (x) and have my RNG run (x) times and sum up all the results into one answer?

Example of what I'd like; Roll 3 times on a 6 sided dice, RNG would bring 3 results so ie 4, 3, 5 Next the program would combine those 3 results to one final # (so example's answer would be 12).

The RNG code i'm using is;

srand(time(NULL));
    roll = rand() % sides + 1;

note: sides is a user entered variable.