使用const int by reference创建静态数组

我想把一排双打运动员 pi_sequence 然后返回指向它的指针。然后我想打印出它的值。我试过了,但我得到了错误 storage size of ests is not constant :

#include <iostream>
#include <stdlib.h>


double* pi_sequence(const int& len)
{
  static double ests[len];
  ests[0] = 1.11;
  ests[1] = 2.22;
  return ests; // address of?
}

int main() {

  double* ests = pi_sequence();
  std::cout << "will write to file: " << ests[0]  << std::endl;

}