use std::uniform_int_distribution in struct and define it's range latter

I have problem where I want to use std::uniform_int_distribution in struct and then give it' range. Below is what I want.

#include <random>
#include <iostream>

std::random_device rd;
std::mt19937 gen(rd());

struct group_s {
   int k;
   std::uniform_int_distribution<> dis;
} group;


int main()
{  
    group.dis(0,19);
    std::cout << group.dis(gen) << ' ';
}

I am getting below error:

no match for call to '(std::uniform_int_distribution<>) (int, int)'
  cpu_group.dis(0,19);

How to define the required functionality ?